quote Originally posted by alienfiero: I was looking at the tps voltage, More then likely be the same at other sensors. I could see a spike but I could not tell how much untell I binked my eyes fast anought see it. Most 88 and pre 88 have the si alt. Check your canister purge valve and filter and replace the rubber vacuum lines. May not solve the problem but may idle a little smother. I just replaced all the old old 10year + rubber vacuum lines and now have a little smother idle.

I probably have an SI alternator then since its an 87 engine. I replaced all the rubber vac lines a while ago. WHat is the canister purge valve? Is that the coffee can looking vac canister? How would i know if thats screwy?

Yes, it the coffie can and if the valve is bad, it will cause vacuum problems.
1. Carefully pull the filter out of the bottem and carfully clean with sope and water, dry between a towel and use your wifes hair dryier, don't get found out, or just get a new filter.
2. Blow into the bottom line going into the purge canister. there should be little or no air passing.
3. Apply 15 "hg tp the top line , if it holds for 20 sec. its ok, if not find another one.
4. If this test is good, and holding vacum, blow into the lower vacuum line, and incress in air flow into the valve should be observed.
If not replace the canister purge.

quote Originally posted by alienfiero: Yes, it the coffie can and if the valve is bad, it will cause vacuum problems. 1. Carefully pull the filter out of the bottem and carfully clean with sope and water, dry between a towel and use your wifes hair dryier, don't get found out, or just get a new filter. 2. Blow into the bottom line going into the purge canister. there should be little or no air passing. 3. Apply 15 "hg tp the top line , if it holds for 20 sec. its ok, if not find another one. 4. If this test is good, and holding vacum, blow into the lower vacuum line, and incress in air flow into the valve should be observed. If not replace the canister purge.

Thanks + for you.

What exactly is 15 hg"?

Check your brake vacuum lines, and the line going into the power vacuum brake booster. Some have clamps on the lines and when I tightened them up, better brakes. I also put clamps the other brake vacuum line fittings, that did not have any.

One more less leak.

bump......

UPDATE:

I installed a brand new fuel filter, used seafoam in the tank and through the manifold vacuum line, installed a new thermostat, installed a new ground, and checked around for anything out of the ordinary.

The car is worse. It stalls at stops now more than it ever did before.

I found that y coolant overflow had some black crud in it, which I can't understand. I don't think there is any oil in it. I also found out that my old thermostat was just bobbling around in the housing. SO I figured maybe I was running without a therostat and possible blocking the passage, but a new one didn't change anything.

The car runs real quiet and perfect at 1100 RPM when it actualy idles now, but then it will start surging and going lower and lower until it stalls. I have horrible throttle response and whenever Iet off the gas the car RPM's immediately dip to almost stalling or stalling.

quote Originally posted by connecticutFIERO: UPDATE: I installed a brand new fuel filter, used seafoam in the tank and through the manifold vacuum line, installed a new thermostat, installed a new ground, and checked around for anything out of the ordinary. The car is worse. It stalls at stops now more than it ever did before. I found that y coolant overflow had some black crud in it, which I can't understand. I don't think there is any oil in it. I also found out that my old thermostat was just bobbling around in the housing. SO I figured maybe I was running without a therostat and possible blocking the passage, but a new one didn't change anything. The car runs real quiet and perfect at 1100 RPM when it actualy idles now, but then it will start surging and going lower and lower until it stalls. I have horrible throttle response and whenever Iet off the gas the car RPM's immediately dip to almost stalling or stalling.

hmm......have you changed the ignition module?

I replaced that two years ago. I'm almost positive that its not an Ign Mod problem. I've had a bad one before and it was a whole different problem. It seems like the car just can't keep the idle up for whatever reason. It runs at a perfect 1100 rpm then it will start surging and stall. Or if i am driving and let off the gas the idle drops really quick and either hiccups a little or flat out stalls.

quote Originally posted by connecticutFIERO: I replaced that two years ago. I'm almost positive that its not an Ign Mod problem. I've had a bad one before and it was a whole different problem. It seems like the car just can't keep the idle up for whatever reason. It runs at a perfect 1100 rpm then it will start surging and stall. Or if i am driving and let off the gas the idle drops really quick and either hiccups a little or flat out stalls.

ah.....just checkin

I swapped my MAP sensor and it changed nothing.
I unplugged my IAC to see if conditions would change, but nothing changed.
I also reset the ECM, no change.

The car will not idle at all now it just stalls everytime I let off the gas. The throttle response is super slow and then when it responds there is some backfiring and popping out of the throttle body. The car is completely undriveable now and I am out if ideas.

quote Originally posted by connecticutFIERO: Me and Jnco never connected, but I am working on my car all day tomorrow so I wil try to get ahold of him. I am having another issue right now with my clutch that I have to resolve first, but I will try to fix both tomorrow. John if you read this, I hope you are home tomorrow cause I'll be calling. I'll update tomorrow.

check yoru fuel pressure man, at both idle and WOT.. should be about 40 psi at idle or better.

my guess is that it is yoru cold start injector or yoru coolant temperature sensor

Connecticut, did you ever try looking for a vac leak?

quote Originally posted by Bigfieroman: Connecticut, did you ever try looking for a vac leak?

Yeah I couldn;t find anything.

i did not take the time to read through the whole thread so i don't know if you have had a chance to look at the fuel injectors.

you could try pulling your spark plugs and checking each one for lean/rich color. tan and dry = lean or just right, black and wet = rich. or just wet for that matter. just wondering if one or all plugs look the same. if they all are the same then it's probably not the injectors. unless the cold start injector is leaking. if your car has been running rich for some time then the cat. may start to clog up and that makes it harder to diagnose. however when my cat was almost completely clogged, my car would idle but not run very many rpms... so hopefully it is not a prob. my car still idles up to 1500 rpm and down to 500, up and down about 20 times before it settles down. only on overnight cold starts though. even if it is around 105 degrees outside. sorry to see this is becoming such a pita for you. best of luck going forward...

edit: just a quick opinion, if you can find another known good ign module to try it would not hurt. two years is plenty of time for one to shell out.

[This message has been edited by cptsnoopy (edited 09-21-2004).]

Man, I've gone through ignition modules in the past like mad.

2 years, worth the investment to replace it.

As for what it could be, if it's an automatic, check your TCC solenoid. Mine went bad previously and did that a lot.

Umm, as for high idle, replace the TPS sensor, check the screw in the TB, and check your EGR valve.

I had a little bit of success today. After I installed a third IAC spare in desperate hope of fixing my problem, I decided to once again try putting my thumb over the vacuum line going to the EGR valve. The car will not run for more than 3-5 seconds, but when I tried blocking the EGR vac line, it ran for about 10 seconds until i released it. I am not sure that says much, but I am buying a new EGR valve tonight and will replace it after work at about 9 pm. Wish me luck.

Good luck man...that would be so awesome if it was something so easy and accessable as the EGR. I am going to be cleaning out my IAC, and after that, if you are successful, I will change out mine. I had an EGR valve torque off from a big bump, and it made the car nearly undrivable, and it would stall every time it idled. Maybe our EGR valves have just slowly been letting go?

If there was a poor seal to the EGR, spraying carb cleaner may not change the idle. As the exhaust heated up, it could seal the crack. My issue still goes away after about 1 minute. Maybe mine just hasn't gotten as bad as yours. I sure hope this fixes your/my problem!

quote Originally posted by Bigfieroman: Good luck man...that would be so awesome if it was something so easy and accessable as the EGR. I am going to be cleaning out my IAC, and after that, if you are successful, I will change out mine. I had an EGR valve torque off from a big bump, and it made the car nearly undrivable, and it would stall every time it idled. Maybe our EGR valves have just slowly been letting go? If there was a poor seal to the EGR, spraying carb cleaner may not change the idle. As the exhaust heated up, it could seal the crack. My issue still goes away after about 1 minute. Maybe mine just hasn't gotten as bad as yours. I sure hope this fixes your/my problem!

Good point, if the car runs better at warm temps its only logical to think either the EGR matal has expanded and sealed the leak if that the case, or that the gunk holding the EGR valve open loosens from the heat and starts to function properly, but then when it gets cold again it could stiffen right up and weld itself open. I had no idea these go so quickly though, mines only 2 years old. I also didn't know they cost $40 for the cheapos and $70 for OEM replacements. Man I have my fingers crossed that this is the problem. I think it didn't change the idle last time I tried it because it was probably warm already. We'll see.

[This message has been edited by connecticutFIERO (edited 09-22-2004).]

When are you going to change it?

I was going to do it tonight after work at about 9, but I called 4 part staores and none of them have it in stock, its a special order that takes 1-2 days. I think I have an extra at home I can use, but if I want to have the new one by Friday I have to order it today, so I am kind of stuck right now. I wish I was at home so I could take it apart and see if its stuck open and see if I have a spare to use or even just clean the one on the car. I bet if I soaked it in engine degreaser over nigt it would be good as new, its all mechanical so it should work.

I hate to spend $40 without knowing for sure that its the problem, so I am stuck trying to decide what to do at the moment. I am going to take a long lunch and sneak in a half hour of grease monkeying to remove the EGR and check the valve, that should help me decide whether to spend the $40.

I have a brand new EGR valve, and a Brand new Braided EGR tube from TFS. Gimme a call, maybe we can make a deal.

Did not see that anyone mentioned the cold start injector. Has this been eliminated as a possible problem?

If it was, it would be running rich so I would think a person might know if it was....

DR

quote Originally posted by Jncomutt: I have a brand new EGR valve, and a Brand new Braided EGR tube from TFS. Gimme a call, maybe we can make a deal.

JNCO TO THE RESCUE ONCE AGAIN!

If at any time your battery has gone dead, try to swap it out for a known good battery. JazzMan had mentioned that if a battery goes dead that it may become damaged. I purchased a new battery and my results were good. A slight hunting idle on warm restart and my cold start has improved. I may have an issue or two affecting my cold start, I'll investigate that and will be sure to pass my results along to you.

Thanks jet but my battery is only 1 year old and never died.

The RESULTS ARE IN. I installed a new EGR valve and gasket just 20 minutes ago and.....
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F%$$IN NO CHANGE!

When I hit the gas all I get is POP from the throttle body and then pluuughhhhhoough chug a chug and take off almost at normal speed, then when I come to a light, bamn car stalls.

Once the car was running for about 15 minutes I saw some improvement, meaning the car didn't stall at EVERY stop but still stalled here and there and then I still have horrible tb backfiring and sluggy performance. So I reset the ECM by removing the battery cable for a minute or so and then reinstalled and restarted.

I did check for codes after I reset the ECM and drove around for 5 minutes and got a code 44. Lean exhaust. I thought it was a rich mixture according to my log from winALDL. It says check for vac leak around the manifold or TB and replace O2 sensor. Should waste another boat load of money buying a new O2 sensor?

Do you have an extra TPS that you know is good? I know you said you've replaced all sensors recently, but you might try swapping that out anyway. I'm not familiar with WinALDL, but does it work like a scantool? If it does, you can see what the TPS is doing. I had a similar problem, and replcaing the TPS helped a lot.

I'm also having this problem on an 86 GT I just bought. It is doing the exact same thing as what you're describing. It's not a priority at the moment, because I have another FIero to drive.

Thanks for helping Sqoach but yes I did swap the TPS with good units. Twice. I'm gonna try the O2 sensor tomorrow and then I'm going to kill myself when that too doesn't work.

Dude, Sorry to hear that didn't work. I know this sounds very basic, but what is your timing set at, and did u watch the timing advance on the winALDL as you drove? I was getting that similar problem when my alternator wasn't charging fully. I would get a pop thru the intake, and the car would stumble until the volts came up to where they should be. Also, I had the timing too far retarded. Other than the stock gauge reading, see what your actual voltage is when running, and check to see your base timing, as well as advance.

The timing was set at like 10-12° and it ran great like that for 6-8 months. I never changed anything, and this problem has progressively gotten worse unlike just having bad timing or crossing a wire. On winALDL the advance was between 30 and 45. The alternator is charging about 13-15. It does spike when the dcar is started, but I would think thats probably normal right?

[This message has been edited by connecticutFIERO (edited 09-23-2004).]

quote Originally posted by connecticutFIERO: According to winALDL I am rnning rich and my coolant temp sesor is right on target man. I havn't checked fuel pressure yet.

check the pressure, and report what it is at idle and WOT directly to the baord in this thread

I am having this same problem, but mine goes away after about a minute of driving. Connecticut, a Bosch O2 sensor is only like $18. I will be changing mine soon, along with the plugs, wires, cap, and rotor.

Can I just buy any old Fuel pressure gauge from the parts store and connect it to my schrader valve? I am planning on buying an O2 sensor and a fuel pressure gauge tonight if I can.

For the gauge, make sure it has capacity to 60 PSI, and make sure it is long enough to reach your valve.

Curde? perhaps. I used a fuel pressure gauge, and some high pressure FI hose. I put a clamp on the hose over the FP gauge, and a clamp over the schrader valve. The hose was about 6" long. No it didn't leak, and no it wasn't permanent, but for a few minutes of testing, it worked fine...

DO NOT use typical hose if this is tried. It will expand/burst.

quote Originally posted by Jncomutt: Curde? perhaps. I used a fuel pressure gauge, and some high pressure FI hose. I put a clamp on the hose over the FP gauge, and a clamp over the schrader valve. The hose was about 6" long. No it didn't leak, and no it wasn't permanent, but for a few minutes of testing, it worked fine... DO NOT use typical hose if this is tried. It will expand/burst.

Do you still have that stuff John?