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Fuel still getting in oil...ej swapped brat


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Does this engine setup have a mass air flow (MAF) sensor on it ?  If so, disconnect it and see if the engine runs better or worse.  If it has a MAF that is malfunctioning, it could be calling for too much fuel.

 

If it doesn't have a MAF...never mind.

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The diagram makes sense, and actually, I just finished setting up something similar on my Tacoma, which I intend only to use around the yard. As such, I wanted to use a small plastic marine fuel tank, which does not have a return fitting. When the system is disconnected for some reason (or the tank is run low enough to suck air), it gets air into it, which can only escape through the injectors/engine. So it runs very poorly for several minutes, and requires many restarts before it clears up. Your symptoms sound a bit like that. It's not correct, but it should work.

 

It's fantastic news that your return line reads no pressure. But the supply should get a bit more than 30 psi (you did say "about" 30, so maybe it's getting to 36ish), and it should hold pressure for quite awhile once the pump is off. This is held by the pressure regulator and a check valve in the fuel pump. It doesn't explain your fuel in the oil issue, but it might explain the running issue if you're having trouble with the fuel pump. I also installed a low pressure fuel filter between the tank and pump to protect the pump from debris.

 

I skimmed through here and didn't see it. Was it ever determined if there are any trouble codes? It's possible it's been trying to tell you what's wrong the whole time.

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  • 2 weeks later...
On 9/13/2021 at 4:29 PM, Dee2 said:

Does this engine setup have a mass air flow (MAF) sensor on it ?  If so, disconnect it and see if the engine runs better or worse.  If it has a MAF that is malfunctioning, it could be calling for too much fuel.

 

If it doesn't have a MAF...never mind.

 

On 9/14/2021 at 3:34 PM, Numbchux said:

The diagram makes sense, and actually, I just finished setting up something similar on my Tacoma, which I intend only to use around the yard. As such, I wanted to use a small plastic marine fuel tank, which does not have a return fitting. When the system is disconnected for some reason (or the tank is run low enough to suck air), it gets air into it, which can only escape through the injectors/engine. So it runs very poorly for several minutes, and requires many restarts before it clears up. Your symptoms sound a bit like that. It's not correct, but it should work.

 

It's fantastic news that your return line reads no pressure. But the supply should get a bit more than 30 psi (you did say "about" 30, so maybe it's getting to 36ish), and it should hold pressure for quite awhile once the pump is off. This is held by the pressure regulator and a check valve in the fuel pump. It doesn't explain your fuel in the oil issue, but it might explain the running issue if you're having trouble with the fuel pump. I also installed a low pressure fuel filter between the tank and pump to protect the pump from debris.

 

I skimmed through here and didn't see it. Was it ever determined if there are any trouble codes? It's possible it's been trying to tell you what's wrong the whole time.

Hey guys...

 

So this weekend I was able to work on it again. Inline pressure was at like 30-31 and stayed there constantly. Once I turned the car off, it would drop to 10psi in about 10 mins, but then stay at 10psi for over an hour.

 

I disconnected the MAF and it started up better than before and died after a little with no throttle. I would give it some gas and it actually would run and idle fine. So idk if it's the MAF but I figured I would order one and can always return it.

 

Chux- That is reassuring that the fuel setup is not complete garbage lol. Also I did spray started fluid around the vacuum lines and didn't see a jump at idle which is good.

I don't have any way to look at the error codes, it was not an OBD2 and when installing the ECU and harness I really didn't know what I was going and I think I may have cut out the double diode, or whatever else can be used to see error codes. Big rookie mistake I know, kicking myself for that one. Even if I had the complete harness, could I still see codes without the gauge cluster?

 

Thanks guys!!

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2 hours ago, bratboy1 said:

I don't have any way to look at the error codes, it was not an OBD2 and when installing the ECU and harness I really didn't know what I was going and I think I may have cut out the double diode, or whatever else can be used to see error codes. Big rookie mistake I know, kicking myself for that one. Even if I had the complete harness, could I still see codes without the gauge cluster?

There's a "read mode" wire at the ECU. Ground that, and it will flash trouble codes on the check engine light (can be done with a test light at the ECU, as well).

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  • 1 month later...
On 9/29/2021 at 9:05 AM, Numbchux said:

There's a "read mode" wire at the ECU. Ground that, and it will flash trouble codes on the check engine light (can be done with a test light at the ECU, as well).

Hey Chux,

 

I got one of those test lights and I tried the ports on the ECU and I could not get a light to pop up unfortunately. Do you think I need to explore getting an aftermarket ECU?

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23 hours ago, bratboy1 said:

Hey Chux,

 

I got one of those test lights and I tried the ports on the ECU and I could not get a light to pop up unfortunately. Do you think I need to explore getting an aftermarket ECU?

Possible, but unlikely. More commonly it's a wiring issue.

 

Key on, engine not running, the check engine light should be on. If this doesn't happen, 99% of the time the ECU is not being turned on (getting all the power/ground that it needs).

 

If you're at your whit's end. Spending some money to modernize the system wouldn't be a bad idea. But it's a big job to get it installed and tuned.

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  • 1 month later...
On 11/8/2021 at 9:11 AM, Numbchux said:

Possible, but unlikely. More commonly it's a wiring issue.

 

Key on, engine not running, the check engine light should be on. If this doesn't happen, 99% of the time the ECU is not being turned on (getting all the power/ground that it needs).

  

 If you're at your whit's end. Spending some money to modernize the system wouldn't be a bad idea. But it's a big job to get it installed and tuned.

Thanks for the insight. I am going to take a look at the vacuum lines to see if I routed a line incorrectly and that is causing it... but if that doesn't work then I will have to modernize it I think. 

 

I appreciate all the help throughout this process, I have definitely learned a lot from you and the others here!

 

 

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