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bratboy1

Fuel still getting in oil...ej swapped brat

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Hello all,

 

I have an 82 brat with a 91 Legacy L 2.2 EJ and 5psd that I swapped into it.

 

I have been fighting this problem going on 3+ months now and I am not sure what I did/didn't do, really could use some insight. I am getting fuel in my oil and can't figure out why. I have replaced the fuel injectors with rebuilt ones, and got them tested so I know they are good.

I have a fuel pressure regulator for the ej in the mail so will do that when it gets here, same with the PCV valve.

 

When I swapped the EJ in, I put an in line Carter fuel pump. Was there some sort of check valve that was in the legacy tank that kept fuel from coming back in from the return side once the car shuts off? I really don't know how fuel keeps getting back in but I am going crazy and spending a lot of $ on oil and filters every time I swap it lol!

 

Thanks for looking and any insight would be appreciated.

 

 

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The only thing I can suggest is dirty fuel clogging the new injectors so they’re stuck open. I hope you have an EFI rated fuel filter after the fuel pump. 

Is it hard to start when cold and hot? 

Only way fuel can be getting into the sump is via the injectors and the cylinders on shut down. Even then, the correct inlet valve of the leaking injector(s) needs to be cracked open enough to let the fuel past them.

After immediate engine shut off, are all injectors also shut off or is some sort of residual power getting in there and activating the injectors (extreme long shot!)? 

How long does it take your oil to be fuel contaminated, and what makes you think you’re getting that amount of fuel in the sump? 

Cheers 

Bennie

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if the engine temp sensor were bad, it might signal the ECU to continue 'choking' the engine as if it were cold. I'd expect poor running and maybe a fuel smell in the exhaust...?

the diaphragm in the fuel pressure regulator can leak,  look in the vacuum line for fuel.

 

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Could it be unburnt fuel that flooded and washed out of the cylinder, left over from troubleshooting the initial swap?

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Does it run OK? Any codes?

 

If you're washing the cylinders walls enough to get fuel past the rings and into the oil, I expect it to be running pig rich. Sound about right?

 

EA81s have a smaller return line, not intended for fuel injection. What's the volume of that pump you're running? If it's higher than stock EJ22, it's possible your return line is restricting and overpowering the regulator. You could put a fuel pressure gauge in after the regulator to see if that side of the circuit is pressurizing.

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On 2/8/2021 at 1:22 AM, el_freddo said:

The only thing I can suggest is dirty fuel clogging the new injectors so they’re stuck open. I hope you have an EFI rated fuel filter after the fuel pump. 

 Is it hard to start when cold and hot? 

 Only way fuel can be getting into the sump is via the injectors and the cylinders on shut down. Even then, the correct inlet valve of the leaking injector(s) needs to be cracked open enough to let the fuel past them.

 After immediate engine shut off, are all injectors also shut off or is some sort of residual power getting in there and activating the injectors (extreme long shot!)? 

 How long does it take your oil to be fuel contaminated, and what makes you think you’re getting that amount of fuel in the sump? 

 Cheers 

Bennie

 

On 2/8/2021 at 2:18 AM, 1 Lucky Texan said:

if the engine temp sensor were bad, it might signal the ECU to continue 'choking' the engine as if it were cold. I'd expect poor running and maybe a fuel smell in the exhaust...?

 the diaphragm in the fuel pressure regulator can leak,  look in the vacuum line for fuel.

  

 

19 hours ago, carfreak85 said:

Could it be unburnt fuel that flooded and washed out of the cylinder, left over from troubleshooting the initial swap?

 

17 hours ago, Numbchux said:

Does it run OK? Any codes?

  

 If you're washing the cylinders walls enough to get fuel past the rings and into the oil, I expect it to be running pig rich. Sound about right?

 

 EA81s have a smaller return line, not intended for fuel injection. What's the volume of that pump you're running? If it's higher than stock EJ22, it's possible your return line is restricting and overpowering the regulator. You could put a fuel pressure gauge in after the regulator to see if that side of the circuit is pressurizing.

 

Hey everyone thanks for the replies! I am gonna address all of them in this reply.

 

Freddo- I actually do not have an EFI rated filter, just a newer legacy filter. That is something I will look into getting now. It is hard to start cold and hot, but more so when hot. What is happening is that I have been fighting this problem, I would change a part or something and then after I would change the oil and oil filter (fuel would come out of the drain, and a good amount too). So for instance we put the injectors on with new seals and changed the oil, it was tough to start it and after I drove it for a bit I parked it, smelled the oil, and it smelled like fuel. When it shuts off not sure if the injectors are still running, any clue how to check that other than just a circuit tester that lights up?

 

Texan- I can replace the temp sensor and the Fuel pressure regulator is in the mail so I will do that too. I will also looking in the vacuum lines.

 

car freak- I am not sure, I completed the swap over a year ago and it was running fine for about 6-7 months before this issue started to occur. However the first day that I put new injectors on and changed the oil it ran so good I had never heard it like that before. That is what made me think it was just the injectors. But by the end of that day, it was getting fuel in the oil again and I have been fighting it since.

 

Numbchux- No codes, don't have and OBDII and running on the stock ECU. I would say its running rich, you can definitely tell. This is the fuel pump I am running: https://www.amazon.com/gp/product/B0015RC4MY/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

Looks to be about 55-60 psi which I think is a bit higher than the ea81 lol! I have a fuel pressure gauge that I can see what its reading on the inlet and return. I have no doubt that could be attributed to what is going on.

 

Thank you all for the reply, I am going to accumulate the parts over the next few weeks. I am going to replace the engine temp sensor, the fuel pressure regulator, put an EFI filter on, check the vacuum lines, check the pressure in the lines, and see what else can be done and provide an update. Thanks a bunch seriously it feels good to have a direction to go after all this troubleshooting. I really appreciate all the help!

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Don't just throw parts at it. Test. Diagnose.

 

'91 Legacy can still display trouble codes even though it's not OBD II.

ASSuming the Legacy that the fuel filter was designed for was fuel injected, than you have an EFI filter.

Yes, the carbed EA81 uses considerably less pressure than the EJ22. You should have upgraded all rubber hoses and clamps on the pressure side to handle that. But I'm not asking about pressure, I'm asking about volume/flow. Carter's web site says minimum free flow is 21 (no mention of unit. The only one that sort of make sense is Gallons per hour, but even that seems low). '92 Legacy FSM specs the MPFI N/A EJ22 with a 21.1gph pump at 36.3psi, so on paper that actually sounds low, but since it's meant to supply fuel injected V8s up to 7.5L....I would think it would have enough.

 

You have fuel pressure gauges on inlet and return? What do they say?

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My 2 cents.  If you have a fuel pressure gauge hooked into the source fuel line, watch the pressure at idle, 2500 rpm, then after shut off to get some base line readings.  Then watch the fuel pressure for 20 minutes after shutoff, it typically should hold within a few psi.  If you're feeling frisky and have a bore camera, or even a good phone camera, safely take out the spark plugs after shut off and look inside to see if you can see fuel draining into the cylinders.

Good luck.

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On 2/9/2021 at 10:15 AM, Numbchux said:

Don't just throw parts at it. Test. Diagnose.

 

'91 Legacy can still display trouble codes even though it's not OBD II.

ASSuming the Legacy that the fuel filter was designed for was fuel injected, than you have an EFI filter.

 Yes, the carbed EA81 uses considerably less pressure than the EJ22. You should have upgraded all rubber hoses and clamps on the pressure side to handle that. But I'm not asking about pressure, I'm asking about volume/flow. Carter's web site says minimum free flow is 21 (no mention of unit. The only one that sort of make sense is Gallons per hour, but even that seems low). '92 Legacy FSM specs the MPFI N/A EJ22 with a 21.1gph pump at 36.3psi, so on paper that actually sounds low, but since it's meant to supply fuel injected V8s up to 7.5L....I would think it would have enough.

  

 You have fuel pressure gauges on inlet and return? What do they say?

 

On 2/12/2021 at 6:51 PM, UnorganizedMechanic said:

My 2 cents.  If you have a fuel pressure gauge hooked into the source fuel line, watch the pressure at idle, 2500 rpm, then after shut off to get some base line readings.  Then watch the fuel pressure for 20 minutes after shutoff, it typically should hold within a few psi.  If you're feeling frisky and have a bore camera, or even a good phone camera, safely take out the spark plugs after shut off and look inside to see if you can see fuel draining into the cylinders.

 Good luck.

 

Hey guys,

 

Good point, the filter should be an EFI filter then.

Thanks for the replies. I have learned a lot from your responses. I was able to find the Carter fuel pump and Chux, it is 21gph for the free flow and 43psi for the pressure: https://carter.opticatonline.com/part/bcqs-0-carter-p74028?ctx_pt=6256&ctx_p=8&ctx_iam=1

 

I hooked up the gauges and got some readings and here is what I found...

 

Cold start return side:

Fuel pump running before engine turns on: 19 psi

Engine Idle @ 800 rpms: 30psi

Engine off: 0 psi, dropped here immediately 

 

Waited 15 minutes and did return side again:

Fuel pump running before engine on: 20psi

at 2500 rpms: 36 psi

Idle: 30psi

Engine off: 0 psi dropped immediately 

 

Waited 10 mins and hooked up feed side:

Fuel pump running before engine on: 36psi

idle: 36-38psi

@ 2500 rpms: 38-40psi

engine off: 26psi

after 10 mins: 16psi

after 20 mins: 10psi

after 40 mins: 6 psi

 

Do these numbers seem okay? I wasn't sure if that gradual drop on the intake side should be immediate or not.   

If it would help I can bypass the inlets and return  and just run some temp high pressure fuel lines for the intake and return sides back to the fuel pump and the tank and change the oil. Then after running I could see if the newer fuel lines would allow fuel to flow back more freely. I also haven't changed any of the parts like I said before hand yet just for studious purposes.

 

Thanks for the help!! I really appreciate you guys sticking around and giving me all this good advice!!

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5 hours ago, bratboy1 said:

Do these numbers seem okay? I wasn't sure if that gradual drop on the intake side should be immediate or not.   

I also haven't changed any of the parts like I said before hand yet just for studious purposes.

The running pressure is right. The bleed down is to fast.

The fuel pump should have a check valve to hold pressure, and the Fuel Pressure Regulator is rated 36 psi, so the pressure should stay at 36 for a very long time.

Change the FPR and monitor the inlet pressure with the gauge.

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17 hours ago, bratboy1 said:

 

Waited 15 minutes and did return side again:

Fuel pump running before engine on: 20psi

at 2500 rpms: 36 psi

 

Idle: 30psi

 

You're getting 30+psi in the return line? Yikes! Definitely have a restriction there. Was it idling that 15 minutes?

Theoretically, as long as the pressure in the return line is lower than in the rails, it should be OK. But as the revs come down, or under engine braking, it could spike up as the ECU shuts the injectors off.

 

I would definitely run a new return line (or a new feed line, and use the old feed as the return) to get those return pressures down.

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22 hours ago, Numbchux said:

I would definitely run a new return line (or a new feed line, and use the old feed as the return) to get those return pressures down.

Or blow compressed air from front to rear with the fuel cap removed. That might dislodge something in the fuel return line. 

Only do this from the return line that disappears into the firewall. DO NOt try blowing compressed air through the inlet fuel lines before the regulator ;) 

Cheers 

Bennie

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does the fuel return line go to a jetpump like in newer models? maybe it is clogged?

(I'm ignorant of older models, just asking)

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On 2/21/2021 at 9:37 PM, Rampage said:

The running pressure is right. The bleed down is to fast.

The fuel pump should have a check valve to hold pressure, and the Fuel Pressure Regulator is rated 36 psi, so the pressure should stay at 36 for a very long time.

Change the FPR and monitor the inlet pressure with the gauge.

 

On 2/22/2021 at 9:16 AM, Numbchux said:

 

You're getting 30+psi in the return line? Yikes! Definitely have a restriction there. Was it idling that 15 minutes?

Theoretically, as long as the pressure in the return line is lower than in the rails, it should be OK. But as the revs come down, or under engine braking, it could spike up as the ECU shuts the injectors off.

 

I would definitely run a new return line (or a new feed line, and use the old feed as the return) to get those return pressures down.

 

On 2/23/2021 at 7:36 AM, el_freddo said:

Or blow compressed air from front to rear with the fuel cap removed. That might dislodge something in the fuel return line. 

Only do this from the return line that disappears into the firewall. DO NOt try blowing compressed air through the inlet fuel lines before the regulator ;) 

Cheers 

Bennie

 

Hey guys,

 

Sorry for the late response. I got new lines put in and the car doesn't turn over so I am currently troubleshooting what is going on. I will post again when I get it running and I'm able to get some readings. Thanks for the help!

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Posted (edited)
On 2/23/2021 at 7:36 AM, el_freddo said:

Or blow compressed air from front to rear with the fuel cap removed. That might dislodge something in the fuel return line. 

Only do this from the return line that disappears into the firewall. DO NOt try blowing compressed air through the inlet fuel lines before the regulator ;) 

Cheers 

Bennie

 

On 2/22/2021 at 9:16 AM, Numbchux said:

 

You're getting 30+psi in the return line? Yikes! Definitely have a restriction there. Was it idling that 15 minutes?

Theoretically, as long as the pressure in the return line is lower than in the rails, it should be OK. But as the revs come down, or under engine braking, it could spike up as the ECU shuts the injectors off.

 

I would definitely run a new return line (or a new feed line, and use the old feed as the return) to get those return pressures down.

 

On 2/21/2021 at 9:37 PM, Rampage said:

The running pressure is right. The bleed down is to fast.

The fuel pump should have a check valve to hold pressure, and the Fuel Pressure Regulator is rated 36 psi, so the pressure should stay at 36 for a very long time.

Change the FPR and monitor the inlet pressure with the gauge.

Ok guys I know it has been awhile sorry for the late response. I don't live in the same city as my BRAT so getting to work on it is not the easiest thing. So I replaced the FPR and ran new fuel lines. The new lines were ran directly to the tank so they bypassed all the old lines. 

 

At first it wasn't starting and I had someone over and looked at it and saw my adaptive tubing to get from 5/16" ID hose to the small size that fits on the return of the tank (I think its 3/16'" ID but I may be wrong). The pic is what I had and my friend said I am for sure choking the return so what we did was take that off, and run the return directly in a jerry can, thinking that would serve us for testing purposed. The car turned over and ran fine so I changed the oil and filter again and it was awesome. It took a crank or two to start but it ran pretty well. 

 

Come a week after with the the return still in the jerry can, it no longer turns over. Oil smells like fuel again and I can't get it to turn over to see the pressure. Any ideas or did what I do sound completely unreasonable in terms of trying to get it to work? I really don't know where to go from here, but would having the return like that really do anything bad?

 

Thanks for helping me along this journey. Been unable to drive the car since December and I am hoping to get it driving again soon if I can.

 

Cheers!

IMG_20210404_151541935.thumb.jpg.41443df4a35cbe8bd05e1da3519943bf.jpg

Edited by bratboy1
added pic

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If there is a vacuum line going to the FPR disconnect it and plug the engine side vaccum line.

Did you hook up any of the EVAP system if the car has it? If so do the same for it.

After those two it has to be injectors. 

 

Did the oil smell like fuel before you tried to start it? If so then leaky injectors. If not ecu is flooding for some reason, pull codes.

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Yes, running 10 feet of 5/16, and then necking it down to 3/16 defeats the purpose. T it into the vent line or something (I've been reading up about converting our boat to EFI, and this is generally how it's done). But yea, for testing purposes, into a separate container is fine (you know, fire hazard and such).

It won't turn over at all? If so, it may be hydrolocked. Try turning it over by hand, if not, pull the plugs and crank it.

Does the ECU control the fuel pump? Or is it staying on when the engine isn't running?

 

I've been approaching this as if it's been just running really rich. But if it's actually filled the cylinder and hydrolocked the engine, then fuel is getting in while the engine is off.

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On 4/16/2021 at 6:53 AM, Ionstorm66 said:

If there is a vacuum line going to the FPR disconnect it and plug the engine side vaccum line.

Did you hook up any of the EVAP system if the car has it? If so do the same for it.

After those two it has to be injectors. 

 

Did the oil smell like fuel before you tried to start it? If so then leaky injectors. If not ecu is flooding for some reason, pull codes.

 

On 4/16/2021 at 9:53 AM, Numbchux said:

Yes, running 10 feet of 5/16, and then necking it down to 3/16 defeats the purpose. T it into the vent line or something (I've been reading up about converting our boat to EFI, and this is generally how it's done). But yea, for testing purposes, into a separate container is fine (you know, fire hazard and such).

It won't turn over at all? If so, it may be hydrolocked. Try turning it over by hand, if not, pull the plugs and crank it.

Does the ECU control the fuel pump? Or is it staying on when the engine isn't running?

 

I've been approaching this as if it's been just running really rich. But if it's actually filled the cylinder and hydrolocked the engine, then fuel is getting in while the engine is off.

 

On 4/16/2021 at 10:00 AM, 1 Lucky Texan said:

after it sits, pull some plugs and look for the wet cylinder.

Alright guys I haven't had a chance to do anything yet but I just wanted to reply and answer some questions...

 

Ionstorm: I will try the FPR method. Also not sure what the EVAP system would be, but that black emissions canister that goes with the engine I have left off and the lines that it hooked on to are open. Didn't think that was an issue, but I can try capping those lines and/or putting the canister in. Would that make a difference?

 The injectors are new rebuilt injectors that I took and got them tested and they are not leaking.

 

Numbchx: Yeah when my friend came to look at it he was like seriously dude? There is no way that's gonna work lol. I have a brass tee that I was going to put on so I will try that out when the return has a tee fitting that hooks up to the intake side and the line from the tank. The ECU does not control the pump, I have the pump wire to the electronics so when I turn the key to run the lights and whatever the pump turns on (and rad fan). If I want I can run the fuel pump for however long before turning on the engine.

 

Lucky Texan: I will do this when I get the chance next.

 

Do you guys think it may be my ECU or am I missing something? I was thinking of going to standalone but I was unsure of that route so trying to remedy this would be my first option. Also this is a phase one ej22 so no OBD II, I am not 100% on how to pull codes for it, especially since I cut out the double diode when shortening the  harness on accident. I still have it and can solder it back if needed.

 

Thank you guys you are the only thing keeping me sane through all of this! I will try out some tests in the next couple weekends and let you know! 

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18 hours ago, bratboy1 said:

The ECU does not control the pump, I have the pump wire to the electronics so when I turn the key to run the lights and whatever the pump turns on (and rad fan). If I want I can run the fuel pump for however long before turning on the engine.

I would correct this. That's almost certainly exacerbating the problem as it sounds like it's still pumping fuel into the engine when it's not running. There is zero good to running the pump longer than the ECU wants it, and plenty of risks.

I would recommend wiring up the self-shutoff control like it should be (that's what one of those diodes is for).

 

Jumper the read mode connectors (or, ground the wire from the ECU if those connectors are gone), and the CEL will flash out codes.

 

Yea, figure out if it's just flooding one cylinder. Check the vacuum line after the FPR for fuel. Grab a noid light to see if the ECU is holding that injector open.

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You know what Steptoe would try here??

The FPR  vacuum line, suspecting fuel leaking from FPR to intake via the vacuum line....find a small, clear, hard acrylic fuel filter used for small engines and fit it in line in the vacuum line. You will need to sleeve tubes to make it work and hold vacuum for sure, but you should be able to monitor any fuel loss

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On 4/26/2021 at 10:17 AM, Numbchux said:

I would correct this. That's almost certainly exacerbating the problem as it sounds like it's still pumping fuel into the engine when it's not running. There is zero good to running the pump longer than the ECU wants it, and plenty of risks.

 I would recommend wiring up the self-shutoff control like it should be (that's what one of those diodes is for).

 

 Jumper the read mode connectors (or, ground the wire from the ECU if those connectors are gone), and the CEL will flash out codes.

  

 Yea, figure out if it's just flooding one cylinder. Check the vacuum line after the FPR for fuel. Grab a noid light to see if the ECU is holding that injector open.

 

On 4/29/2021 at 2:06 AM, Step-a-toe said:

You know what Steptoe would try here??

 The FPR  vacuum line, suspecting fuel leaking from FPR to intake via the vacuum line....find a small, clear, hard acrylic fuel filter used for small engines and fit it in line in the vacuum line. You will need to sleeve tubes to make it work and hold vacuum for sure, but you should be able to monitor any fuel loss

 

Hey guys,

 

I just wanted to post a little update, I still am going to try a few things more but here is what I did so far:

New fuel lines

New FPR

Remanufactured injectors- tested them as well

-----------

This weekend I did what you suggested, Numbchux, I basically wired in the relay for the fuel pump and it works, you can hear it prime when I turn the key a bit and then will hold off until the car cranks. 

I took the plugs out and they were pretty black, I cranked it with the plugs out and the fuel pump disconnected and there wasn't any fuel shooting out. Changed the plugs and the oil, and same thing happened. I started it fine, then 30 mins later it struggled, then another 30 mins it wouldn't turn over.

Tried an hour later, wouldn't start, then I took that little tube off the back of the FPR. There was no fuel in it, it smelled like fuel though. I am not sure if that was too long after running for me to look but I can. Not sure if that was even the right tube to look at but I will look more the next chance I get. Also working on getting a noid light to check the injectors.

 

I think that is everything so far, does it seems like I am missing a piece to the puzzle still? I appreciate all the help you guys are awesome and I couldn't do it without you!!

 

Thanks!

 

 

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