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Morning bog down.. rpm issues


RXJ
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Well, my 91 Loyale (2WD, SPFI) takes 5 or 6 revolutions to start cold versus half a turn when it's warm (or about 2/2.5 secs cold when warm, MAYBE 1 sec or less to kick).

 

Dead cold, it'll rev to about 2.5K, I tap it, it falls to about 17, then back up to 2,2250 then it'll drop to about 15 when I start rolling, then 800 or so. When I get on it, it'll fall off and feel like fuel starvation around 4 or 5K when cold, but no bucking or anything crazy..

 

When warm, she runs well all the way through the range, but sort of hunts at idle, dipping and shuddering around 700.. and the injector gets REAL loud (it's loud clicking like it does, but audible with the hood closed!) I've confirmed the timing isn't cutting out, and the ECT, MAF, TPS and O2 are all operating within range (even though the O2 starts varying voltage at less than 400F.. Haynes says 600 or so..) and the manifold vac fluctuates EXACTLY (never less than 19 or so, but definitely not rock steady) with the shuddering and the popping from the tailpipe.

 

anyway, when I unplug the MAF sensor, the CEL kicks on and the idle smoothes right out and the vacuum holds steady at 20 in-Hg.

 

Anyway, thats what mine does.. lol

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Does it sound like it's "panting" ?

I forgot my car used to do this.. in warm weather too...sitting at a stop light it would, at random moments, be panting like the family dog..

 

Not really. Once it gets to the point of dropping to low idle it drops down, revs up, drops down, revs up, drops down. Maybe 1/2 a second duration between the drop/rev/drop/rev thing.

 

I have noticed at times, a somewhat odd idle sitting at a stop. Almost like it's missing on one cylinder, but not quite. Very random in it's occurance, so it's not something I'm going to chase down easily.

Maybe that's the "panting" you talk of.

 

Only other FIed Subaru I've owned was the '88 XT6, 2.7L MPFI. Been 5 years or so since it was on the road, don't recall much on how it did the cold start thing.

 

My Son, Chris, had an '88 GL10 FWD Auto Wagon with SPFI. It had drivability issues when it was with the PO. We tried working the bugs out but gave up and swapped it over to a Weber. Problem(s) solved.

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I thought i would make a video of a proper cold start.

 

mine is a turbo so it has lower compression, how that affects the starting im not sure.

 

http://www.youtube.com/watch?v=bd4ThWHR0lc

 

forgive the snorting and hacking, im still kinda sick.:-p

 

Big difference when you get rid of that clutch fan. Much quieter.

 

I think next time I'm out to the hooptie with my phone, I'll make up one of these too. Good idea!

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post office

Parole officer

probation officer

persistant offender

police officer

previous owner??

i'm increasing getting lost in this world.

you have a son..it could be any one of the above

:-))

 

HA HA. Good laugh there on this end.

No offense meant!!!!!!!!!!!!!!

2 thru 5 have been here at this humble abode.

 

Damned Grandkids anyways.....

 

 

All in good humor though...

 

PO = Previous Owner

Edited by TomRhere
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Very good video, I didn't think to time the warm up, I might have to do that next time. That looks like a perfect running spfi ea82 to me.:headbang:

 

its interesting that it took about the same time between our cars to go back down to idle, when you were at about 40F and I was at 22F.. not sure where I'm going with this but i have ADOS attention deficit oohh shinny!

 

I think everyone should do this. because sometimes you need something to compare your car with.

Or you'll end up doing what I did and replacing every single sensor.:D It worked, but my wallet never forgave me, I had to get a new one.:-p

 

A quiet Subaru is like a stealth bomber, I feel invisible when I'm driving.:headbang:

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That looks like a perfect running spfi ea82 to me

 

Thank-you sir. Ben may look like hell, but he is very well maintained.

Regular 3k mile mobil 1 oil changes +filter. 10k mile tune-ups with nothing but name-brand (NGK, Mobil, etc) parts. NGK plugs. If anybody ever wants to take on the challenge of fixing him up, I'd be interested...

 

 

I concur to more people making similar videos. Not only for comparison, but I (who doesn't?) love to see these cars in action.

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Regular 3k mile mobil 1 oil changes +filter. 10k mile tune-ups with nothing but name-brand (NGK, Mobil, etc) parts. NGK plugs.

 

+1 drive it like you stole it, maintain it like its a Bentley.:headbang:

 

I had another thought, perhaps some highway on-ramp/0-60 videos?

partially for comparison, mainly for fun:D

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+1 drive it like you stole it, maintain it like its a Bentley.:headbang:

 

I had another thought, perhaps some highway on-ramp/0-60 videos?

partially for comparison, mainly for fun:D

 

I don't know if my video camera will record long enough =P LOL

 

That could be done. Hopefully I won't snap an axle..Last time I timed the Loyale it took about 15 seconds and the GL took 20. hahaha

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Ha! My turn at this fancy video sharing thing.

 

 

:banana:

 

That is exactly how my 90 loyale cold start is. I thought it was just me. Thanks for the video. Now why does it bog down so bad when I first start driving in the morning? Runs fine after full warm up. Also, how far up does your water temp gauge needle go. Mine will go up to dead middle then drop to 1/4 and stays there at all times. New thermostat & engine temp sensor. Any Ideas?

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That is exactly how my 90 loyale cold start is. I thought it was just me. Thanks for the video. Now why does it bog down so bad when I first start driving in the morning? Runs fine after full warm up. Also, how far up does your water temp gauge needle go. Mine will go up to dead middle then drop to 1/4 and stays there at all times. New thermostat & engine temp sensor. Any Ideas?

 

I account it to it just not being warmed up! I never drive the Loyale until it's at least a little warmed up because a.) I don't like the bogging and b.) I *hate* how much the car vibrates when you're at a stoplight and the engine is trying to idle at 2k but it's in drive so it's idling at 1500 rpms.

 

My temp gauge had always stayed at 1/4 of the gauge. It would never go higher. I say had because she now has a restriction in cooling flow and a leak, a replaced radiator, no clutch fan, and an aftermarket cooling fan (all due to the front end accident) and now it is almost always at 1/4 of the gauge but sometimes will creep up to just over half.

 

Best suggestion I can give is that you just wait at least a minute before driving after starting, and don't get into the accelerator hard at all until your temp gauge is at least above the "C".

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Sounds to me like a lean engine scenario,if there are no mechanical or electrical issues maybe the problem is lean because over the last twenty years fuels have changed and are generally higher specific gravity ( ie thicker) so they do not flow through either jets or injectors like they did with older fuels.

Many a vehicle car or bike with carby richening up the jetting does wonders bit harder with EFI though,I have always thought though about using a motorcycle powercommander at least on EA81 or 82 turbos with 4 injectors just get one from a BMW K1200 RS with Bosch injectors as the connections will fit a subie and you have an easy to fit and tuneable Subie piggyback system for a bargain price.

Single point though have to play injectors ar fool the system electrically to do something.

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I account it to it just not being warmed up! I never drive the Loyale until it's at least a little warmed up because a.) I don't like the bogging and b.) I *hate* how much the car vibrates when you're at a stoplight and the engine is trying to idle at 2k but it's in drive so it's idling at 1500 rpms.

 

My temp gauge had always stayed at 1/4 of the gauge. It would never go higher. I say had because she now has a restriction in cooling flow and a leak, a replaced radiator, no clutch fan, and an aftermarket cooling fan (all due to the front end accident) and now it is almost always at 1/4 of the gauge but sometimes will creep up to just over half.

 

Best suggestion I can give is that you just wait at least a minute before driving after starting, and don't get into the accelerator hard at all until your temp gauge is at least above the "C".

 

I always let it warm up in the morning until the idle drops. But there is always lag until full warm up. Even when it not cold outside. I'm sure it's just the nature of the BEAST:headbang:

Now I just have to fix the rough idle issue I have. Just got this car a month and a half ago. Trying to get issues solved one at a time. Couldn't even drive it when I got it. Got it going in two days now it a daily driver 100+ miles a day. Love it. If I resolve the bog down issue I'll let you know. Thanks

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I was originally gonna start a new thread about my idle issue, but I figured I would just tap into this one, since it's a similar issue. So it looks like what you guys are talking about is the car idling high when the engine is cold. My car does the opposite. If it does manage to idle, it'll idle low.

 

So basically what happens is in the cold, morning hours, I go out to my car, start it, and have to hold the gas down for 10 minutes or so until, like flicking a switch, the engine decides to idle normally. And yes, that's 10-15 minutes; not the 5 minute wait time you guys seem to be having. Now, I don't have the time, patience, or [gas] money to be revving my engine for 10 minutes almost every time I start the car (since it is going on winter). So what I usually do is rev it until it'll idle at about 600 RPM, then I start driving. I know, not good for the engine. The annoying thing is, is whenever I have to push in the clutch, the RPMs fall fast, causing the car to stall. I have to feather the throttle to keep the engine alive.

 

After about 10-15 minutes of driving, it'll suddenly idle like normal. Sometimes this happens when I'm waiting at a red light, and it will be like a switch is being flipped inside the engine and is telling it that it's okay to idle normally. So yeah, any ideas?

 

Here is a video of me starting the engine. It wasn't too cold out, maybe about 50 degrees. I can't imagine just how bad this will be in the snow....

 

http://www.youtube.com/watch?v=A58W678jWnc&feature=youtu.be

 

Another slight issue I have is when the engine is idling normally, if I have the defog on, it'll idle at about 2000 RPM. Once I switch it to the "HEAT" setting, it'll drop back down. It's kinda annoying going to shift gears and the RPMs basically stay where they are until you let the clutch out. Any ideas towards this? I have a feeling of a vacuum leak, but is anyone else having a similar problem?

 

Sorry for the long post, and I don't mean to hijack this thread or anything. Just saving myself from posting yet another new thread.

 

Oh, and you guys were talking about 0-60 videos? I haven't done one in my Loyale yet, but I did one in my old '81 GL. A whopping 23.56 seconds. It had an exhaust leak and a host of engine problems, so I would say it did pretty good. And I guess I should've started in first gear, but first was so short, and the only way I could get into first gear without it grinding is if I put it in gear at precisely 9-12 MPH.

 

http://www.youtube.com/watch?v=5ZiGNmSvFto

Edited by jj421
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thanks to you guys for taking the time to post vids...mine's different for sure..it'll climb to 3000 on it's own if allowed...

 

beiginning to think i should check my timing...my gas mileage hasn't been stellar lately

 

jj421...holy moley man....maybe you should check timing also...I dunno

Edited by RXJ
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JJ421:

 

This sounds like a CTS problem. It doesn't know the engine is cold, so it doesn't get the mixture or idle right. Once it is warm, away it goes.

 

Does it also take a long time for the temp. gauge to come up? There may be a thermostat problem as well, it could be stuck open, so it takes forever to warm up.

 

Look at the IAC as well. It might be crudded up.

 

The heater setting affecting the idle is weird. No ideas!

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JJ421:

 

This sounds like a CTS problem. It doesn't know the engine is cold, so it doesn't get the mixture or idle right. Once it is warm, away it goes.

 

Does it also take a long time for the temp. gauge to come up? There may be a thermostat problem as well, it could be stuck open, so it takes forever to warm up.

 

Look at the IAC as well. It might be crudded up.

 

The heater setting affecting the idle is weird. No ideas!

 

Yeah, I've been thinking about the coolant temp sensor, since now matter how much carb cleaner I spray into my IACV, it doesn't fix the issue much. I've replaced the IACV with a cleaner looking, junkyard IACV from Skylar, but that doesn't seem to have changed anything. That, again, leads me to believe the CTS. Looks like a CTS is $16 from O'Reilly, and a thermostat isn't more than $10, so I might replace both of them this weekend and see if it fixes it. From what I've read, the CTS is right next to the thermostat, so it'd make sense to replace both at the same time. I probably clean up the connector to the CTS as well (should be the green plug, right?) since that can cause problems too, I've heard. Am I correct in thinking that I need to drain the coolant before replacing the CTS? I remember reading that somewhere. And is there any way to test the CTS? Well, I guess it wouldn't matter, since I don't see any harm in replacing it. :D I know how to test the thermostat, but again, no harm in just replacing it.

 

The temp gauge starts to go up once the car starts to idle, I think. I don't really look at the temp gauge often. But I believe it takes about ten minutes to start going up.

 

Yeah, I'd like to fix the high idle on defog problem. I mean, unless I'm blanking out or something, the only thing that crosses my mind to cause that is a vacuum leak of some sort.

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CTS probably isn't the correct one at 16 bucks. The correct BWD (the supplier that O'Reilly's offers) sensor is closer to 100. It'll have the two leads coming off with a green plug. The sensor you were looking at was probably the temp sender (for the gauge)

 

And when you kick on the defrost/defog for the front, it kicks on the A/C compressor causing the ECU to spike the RPM.

 

Make sure your IAC is clean and doesn't have a vacuum leak (was the problem with mine, leak at the IAC gasket)

 

Also, either get the Stant XactStat or dealer only. I installed a Beck/Arnley (MotoRad make) and had an underheating problem. The difference between the cheap ones and the real ones is pretty huge.

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Yeah, there was a sensor for $15 or whatever it was and another one for $80 or so. So I'm guessing it's the more expensive one then?

 

See, I took the A/C compressor out of my car, so I'm guessing that would be the reason then. I never needed the defog before I took it out, so I can't say what it was like before. But the compressor wasn't hooked onto a belt, so that was one of the reasons why I took it out.

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Yep. You can always call them and double check, but it'll probably be a day or two out since that BWD item is inventoried as warehouse, at best.

 

And yeah, the ECU will kick up the RPM until the "signal amplifier" (the little black box that hovered infront of the A/C Compressor clutch) reported equal RPM to the tach signal and the ECU would balance them. So it'll keep ramping up the RPM until the imaginary compressor catches up. I'd pull the A/C fuse/relay and see if the ECU will give up..

 

but I believe your low idle and high idle are unrelated, you can pull the connector at the CTS and read the resistance on the CTS side and note the water temp (dead cold/ambient and running temp) and you can compare the resistances to the table/chart to see if it's in spec. Also make sure you have infinite (zero conductivity) resistance to the battery ground (i.e the sensor hasn't grounded itself to the motor). You can also check the 12V source on the harness side and low resistance back to the ECU/body ground to make sure the harness is clean.

 

Good Luck!

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Yeah, so it looks like the one from O'Reilly is $87, is an Import Direct Ignition, and would take a day to show up. However, on RockAuto, there is an Airtex/Wells sensor for $70, and an Ultrapower sensor for $37. Both would, of course, take a week to arrive at my house. Would these different brands really affect anything, or is the CTS "just a sensor," and it doesn't matter what brand you choose? I wanna go off of RockAuto because 1) it's cheaper and 2) I wanna buy an air filter, some spark plugs, and spark plug wires off of there as well.

 

So basically the only way to fix the defog idle issue is to put the compressor back in? I'll look for a fuse, but I think that could prevent the defog from turning on as well. And believe me, I need the defog. :D Oh well, not really a big deal. Not as bothersome as my cold idle issue.... All I need is a good way to prevent fog from building up on the windows and it won't be a big issue.

 

I'll check the resistance when it's light out. Where would I find the charts to see if it's in spec? Thanks for the help!

 

*EDIT* I just had a great idea. Tomorrow I'll go pull some CTSs off of various Subarus at two Pick-N-Pulls tomorrow. I don't know why I didn't think of it before, haha.

Edited by jj421
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