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Discussion Starter #1
I am having some trouble with the XR7 stalling out on me at red lights. In fact, it seems like it has a sensor that knows when the light is about to turn green and just dies. When I come to a complete stop, the RPMs begin to move between 500 and 800ish. And right before the light turns to green, it dies. However, it is not at every green light, nor is it every time that I stop. Sometimes I will come up to a green light and it will be just fine no RPM change or stalling.

The symptoms started about a month ago and I have been trying to track down the problem. I started with a tune up (coil packs, plugs, wires, K&N air filter recharge, and a fuel filter.) No luck. Then I started listening a little closer and heard a vacuum leak. I got under the hood with my bottle of propane and started fishing for the leak. I found a major leak in the T Vac piece. All the other lines were good as far as I can tell. However, it still has the same symptoms, and I think that I can hear a vacuum leak still. I simply can not find the leak though.

I have been searching and searching on the forum but I can't find anything. Please help! :)
 

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Discussion Starter #3
I wouldn't think so because it runs fine up at higher rpm. If I'm moving, it does just fine. Not that I am ruling it out.
 

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It's not your fuel pump. It's more than likely your IAC valve (idle air control) or your MAFS. I which case start with your MAFS buy cleaning it with some electronics cleaner from your local auto store. If this issue persists then it is your IAC, replace it. Its about a $50 part and easy to replace. If you have the stock 95 NPI all aluminum intake manifold it is next to the throttle body plenum on the back of the intake manifold held in place with 2x 10mm bolts. I forget if it is the left or right hand side.
 

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Discussion Starter #5
Yes I also cleaned the MAF when I fixed my vacuum leaks. So, I will try my IAC next. I think that I have exhausted all of my cheap options.
 

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its possible your EGR might be sticking open too, my old 3.8 used to do that. it would drive fine most of the time, then all of a sudden when i came to a stoplight it would idle rough and if i didn't get to the throttle fast enough it would die. easy enough to check by disconnecting the vacuum to the EGR when everything is idling ok and plug the line with a nail or something. if the stalling problem goes away you found your problem.

hope its not that though, their a nightmare to get at in the 95's >.> IAC isn't easy, but its not hard either. besides i want to say the EGR would pop a code on the 95's if it failed to close or open. not sure about that though. i know my 90 didn't...
 

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i want to say the EGR would pop a code on the 95's if it failed to close or open. not sure about that though. i know my 90 didn't...
The reason your 90 probably didn't throw a code is because it was OBD-I (OBD-I sucks), where as the 95 (at least I know mine is) is OBD-II. On the 95 it will throw a code, mine once threw a code for the EGR being stuck closed.
 

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I wouldn't think so because it runs fine up at higher rpm. If I'm moving, it does just fine. Not that I am ruling it out.
I had a POS Tempo that was doing the exact same thing you described, fuel pump turned out to be the problem.

Joe
 

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In my experience IAC will rev high. And I would think it would only be the case if the engine was cold. My IAC isn't even plugged in and when the engine is warm I have never had a stall problem. Only on initial start up.

Kevin
 

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+1 on checking the IAC for starters. At least clean it really well.
 

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The reason your 90 probably didn't throw a code is because it was OBD-I (OBD-I sucks), where as the 95 (at least I know mine is) is OBD-II. On the 95 it will throw a code, mine once threw a code for the EGR being stuck closed.
yeah, i know. i just wasn't sure if the OBD-2ish... in 95 had an electronic EGR or not. i think it was just the evap flow sensor that was missing.

and yeah, if their isn't an EGR code i suppose your best option is the IAC. mine never failed causing stalling issues, but it did make mine idle really high when it failed. its buried on the driver side of the intake under the violin case and some vacuum and electrical. simple enough to remove. mine was full of oil when i got it off :p
 

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Discussion Starter #12
Ok I replaced the IAC. I am still having the same problems. I can still hear the leak but can't find it, and I still have the stalling issue. The leak sounds like it is coming from the driver side of the car. However, as you know, the EGR is on the passenger side.

Is there anything else on the driver side that could create this problem? Or is EGR my next best guess? And any advice on how to make the EGR removal easier? Thanks in advance.
 

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IIRC on the 95 the cruise control still used a vacuum servo. If so that's in the driver's fenderwell. Brake booster is also on the driver's side.
 

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I would first try removing the vacuum line at the ege valve and capping it to see if it is the egr valve. With no vacuum on it, it should remain closed. You can also cap the vacuum source to the egr solenoid as well.

It can still be your maf, just because it's clean doesnt mean it's working properly.
 

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Discussion Starter #15
I am not quite sure what I am supposed to plug on the egr. Do i plug the vacuum line? And what symptom will appear if the egr is bad?

I also have not ruled out the maf, I think that I want to repair all of the vacuum leaks before I try putting in a new maf.
 

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No, not plug anything on the EGR valve. Remove the vacuum line that goes to the EGR valve, and cap it [the vacuum line].

If your EGR valve is faulty, this should remedy it temporarily. I say there's still a vacuum leak somewhere.
 

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Discussion Starter #17
Ok that is what i thought you had meant but I wasn't sure. Thanks GM. I also agree with another vacuum leak. Is there any way for me to test the overdrive servo?

My second thought was the brake booster. Is there any way to test that?
 

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if your looking for a vacuum leak your best bet would be to get back in their with a propane torch, and start spraying it around places that have vacuum. brake booster, intake, vacuum lines and switches, that vacuum canister in the passenger fender well, etc.

the brake booster is a large vacuum diaphragm, just get that propane around the whole thing, if its rusted through on the bottom of something you'll find the leak easy enough.

just don't forget you may have multiple leaks, if you find and fix one, still try to look for more.
 

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Discussion Starter #19
that is the problem. i have gone around with my propane and i can not get it to stall or change rpm anywhere i spray it.
 
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