Idle / Stalling problems. Advice Please.

[7M Brew Co]

My car has been idling funky for a little over a week. I'm not sure if this may have anything to do with it but it seems like it started after I filled the car up with gas. I put mid grade gas in the car. I was driving home from work and as I was pulling up to a stop sign the car would kind of lope for a sec like it was about to die. Well this then turned into the car stalling at stop signs or when backing out of my driveway at a idle. I drove the car for a few days and as the gas level got down it seemed like it was getting better. So I go and fill the car with 91 octane and put in some fuel system cleaner and the symptoms seemed like they got worse again.

When the car dies the check engine light comes on, as well as the battery warning light comes on. But after the car stalls it starts right back up. I checked the car for codes.... nothing. Also the car doesn't start like it usually does. Currently when I first try to start it it'll kind of stall right as its about to start. Takes 2 trys to get it going.

I tried to leave a minute ago and just gave up on that idea. The car was cold so the rpms were in the normal range and then it was constantly loping down to the point of almost stalling. When I tried to back out it just kept stalling. The car does not stall when I give it gas.

Things I recently did to the car. Put 2.5" hardpipe and new intercooler, hks ssqvIII bov recirculated. I've been running this for about a month with no problems so I don't think that this is related.

I was looking for a possible vacuum leak and nothing obvious stands out. I did the other day notice that the vacuum line that runs to the bov was disconnected near the intake manifold. I reconnected it and zip tied it to keep it on tight. The other day I checked the timing and it was good. Replaced the spark plugs too. Still have the problem.

The only thing that I see visually is a little crack in the accordian hose right where it connects to the turbo. The crack doesn't look all to significant. Could this be the cause of these issues? Any help would be appreciated. I'm gonna go get some carb cleaner to check for a vacuum leak that may be hidden. Thanks.

 

[89supra7mgte]

Try putting some duct tape on the crack or whatever can seal it up. you are releasing metered air which will cause stalling such as an unrecirc bov.

 

[7M Brew Co]

Yeah I was thinking about trying that. I'll give that a shot because I just now sprayed down all of the vacuum lines with carb cleaner and didn't see any change in the idle. If that fixes the problem then I'll just replace the accordian. I don't get why it was getting better as my tank neared empty and as soon as I filled up again my car started running like shit again. And no damn codes. Hopefully its just the accordian.

 

[89supra7mgte]

May also have a fuel system issue. maybe on a full tank when pump is submerged it for some reason cant supply enough fuel, and when low it can pull the fuel faster? maybe the baffling in the tank? but first things first you found the crack after the afm that needs fixed first.

Also maybe its just coincidence with the fuel level and acting up?

 

[7M Brew Co]

I pulled the accordian off a little while ago. Before I did that I started the car up. I unplugged the MAF and the idlle didn't really seem to change all that much. It seemed like it was idling about the same. I also rechecked for codes and there's still none. If it was the MAF wouldn't that give a code? I'll try to fix the accordian tomorrow.

 

[bombinuass]

brake boosters can cause this too..

 

[7M Brew Co]

Ok so I taped up the crack something fierce today. Put everything back on. Well car is still running like crap. However this time I went ahead and shorted the E1 and T1 terminal in the car and when it stalled it gave me two codes. This is the first time I've ever gotten any codes from it. Code 31 which is the MAF and 24 which I believe is a air temp sensor or something. So yesterday when I unplugged the MAF and the idle didn't change... maybe this was a sign that my MAF took a dump. I'll test the plug to make sure but if the plug is good I think I may have to get another MAF sensor.

On another note I noticed that I was getting smoke from the exhaust side of the engine with the smell of oil. I was assuming that this was probably related to loose valve cover bolts. I don't visually see any oil leaking anywhere. It looks like the smoke is coming from under the exhaust manifold heat shield. Anyone had a issue similar to this? I'll try tightening down the bolts sometime soon when I get this car back on the road.

 

[Nick M]

If you didn't have 31 and 24, but now do after unplugging, don't you think that is why you got the codes? I would suggest a leaking intake, and the leak is expanding like a crack. But you seem to found one, look for more.

 

[7M Brew Co]

If you didn't have 31 and 24, but now do after unplugging, don't you think that is why you got the codes? I would suggest a leaking intake, and the leak is expanding like a crack. But you seem to found one, look for more.

Well I only unplugged the sensor temporarily to see if there was any change in the idle. There was no change in the idle. Shouldn't there have been some kind of change in the idle if the maf was functioning? I looked at all the intake pipes don't see any more leaks. I sprayed alot of carb cleaner along the vacuum lines and also the intake and couldn't find anything. So if the codes popped up from me unplugging it, would those codes keep popping up until I cleared them regardless if there is an issue or not? I also checked the fuel pressure, which was good. I'll figure this shit out hopefully sometime soon. Thanks.

 

[89supra7mgte]

When you unplug the afm iirc you will set the codes for both, but will only see a change off idle? and no codes will not come back unless it is a consistent fault (hard fault). if you have no afm codes prior to unplugging then chances are that is not the problem. Have you pulled and checked cam timing? see if belt may have slipped. Yea you may have checked ign timing but not the mechanical time of cams, my buddies car did the same shit, pulled cover and found belt slipped.

 

[S.A. supra]

I had a similar problem, it ended up being the throttle body gasket. So i would think it would be a vacuum leak some were.

Did you do the 5 speed swap?

 

[Nick M]

Shouldn't there have been some kind of change in the idle if the maf was functioning? I looked at all the intake pipes don't see any more leaks.

If you unplug the airflow meter, the car will still run. It won't run better, the airflow meter is a primary input, not a correction factor where a known good value can be substitued. It won't run better if you unplug it. If you have the means, you can check the Hz output of the meter. About 30 or so at idle, or 20-40 Hz in the book.

Jumped engine timing and a vacuum leak cause a similar symptom. The A/F ratio is wrong. If you speed up the engine with the engine timning jumped, the car will run a little better. Unless it magically jumped forward of engine rotation.

 

[7M Brew Co]

I had a similar problem, it ended up being the throttle body gasket. So i would think it would be a vacuum leak some were.

Did you do the 5 speed swap?

I'm actually gonna do the 5 speed swap here in about a week. I just got back from Iraq about a month ago and now they finally gave me some leave lol. So as soon as I hunt down and fix this problem with my car I'll take it to the shop on base and do the swap there.

 

[7M Brew Co]

Ok. I'm still at a lose for what this exactly is. I reset the ECU and I'm no longer getting any codes. It's not the MAF sensor. I checked the coil packs and harness... that was good. Fuel pump is good with good pressure. I pulled the cam gear cover off and the belt is in great shape and it doesn't appear that the belt slipped. I was trying to line up the line on the crank pulley with the timing marker by just bumping the key to turn the engine. I didn't get everything perfectly lined up but looking at it and making some judgement it looked like it was all normal. No missing teeth on belt and it doesn't look too old. Spark plugs are new, plug wires are in good shape. I looked again for vacuum leaks and couldn't find any, or any other air leaks in the induction system.

I used the multimeter on my CPS and I had a question about my findings. Using this link http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=IG&P=16 I ran a resistance of the pick up coil on the CPS as shown on the link. On all three my reading was slightly above the normal. All three are supposed to read at 140 to 180 ohm resistance and I was getting a reading of about 187 on all three. Before I start jumping the gun on the CPS i wanted to see if anyonne else has had any experience with testing the CPS and if my reading would be considered time to replace it. Thanks.

 

[supralee]

Did you ever find a solution to your problem?

 

[honeydew]

It does sound like a breathing issue. The AFM can get fouled and throw some bad air temp., dens., etc. data and may not give you a code. The AFM can swirl air *funny* due to an obstruction (like a hunk of K&N) and would give you a lopey idle, drop in Hz to stall, maybe some black smoke from flooding.

Did you say you had a SAFC?

A CPS or a jumped tooth would act like a nasty timing issue. MAP sensor fail is harsh under load, not drivable.

 

[7M Brew Co]

Ok. I got tired of looking without finding the problem. I sent it down to the local toyota dealer and had them take a look at it. They looked over most of the stuff I did and everything seemed fine. I had them do an injector service by bypassing the gas tank and cleaning them with some kind of chemical cleaner. Well, that fixed the problem. I guess my injectors were clogged. Could have been from sitting for a long ass time while I was in Iraq. Now it runs fine again. Shit thing is I had just put in an injector cleaner and the car wouldn't run to let the stuff work. Oh well, at least I can drive again.

 

[honeydew]

Ohhh, cool. I thought you said you checked the fuel but I read back and you just mentioned checking at the pump only. I hope it didn't cost too much, but at least it's done.

 

[ForcedTorque]

Was there fuel in the tank while you were in Iraq (Thank You, BTW)? If so, it could have deteriorated, and may cause further problems now that it fixed.