99 PA starts weird/now a misfire

[hammerhankinson]

My PA has been starting kind of funny for a couple years now. After turning the ignition over it fires but then immediately feels like it wants to die for a split second before getting going and once it does get going it idles a little hight (1.7 RPM, not sure what the norm idle rate is but it feels high and doesn't stay steady. usually climbs slowly for a couple minutes before eventually getting down to around 1 rpm). And its a bit sluggish getting going from a stop. A few months back I had a MAF low input code which eventually caused a random misfire and after replacing the MAF sensor it took care of the misfire and most of the sluggishness. Then a few weeks after that it wouldn't start without pumping the gas and after replacing the fuel pressure regulator it fixed that problem and felt like it was starting a lot better as far as the weird start issue it's had for a couple years.

Now its about a month later and it's been starting weird again and I now have a cylinder 1 misfire. I haven't checked the spark yet but about 9 months ago I replaced the plugs, wires, coil packs, and ICM from a misfire issue i was having and I'll definitely check but with everything almost brand new I don't think that it could be one of those things.

I was thinking the Idle air sensor or throttle position sensor for the weird start and high idle but would those also cause a misfire? Any other ideas?

[Scrapper]

Originally Posted by hammerhankinson

My PA has been starting kind of funny for a couple years now. After turning the ignition over it fires but then immediately feels like it wants to die for a split second before getting going and once it does get going it idles a little hight (1.7 RPM, not sure what the norm idle rate is but it feels high and doesn't stay steady. usually climbs slowly for a couple minutes before eventually getting down to around 1 rpm). And its a bit sluggish getting going from a stop. A few months back I had a MAF low input code which eventually caused a random misfire and after replacing the MAF sensor it took care of the misfire and most of the sluggishness. Then a few weeks after that it wouldn't start without pumping the gas and after replacing the fuel pressure regulator it fixed that problem and felt like it was starting a lot better as far as the weird start issue it's had for a couple years.

Now its about a month later and it's been starting weird again and I now have a cylinder 1 misfire. I haven't checked the spark yet but about 9 months ago I replaced the plugs, wires, coil packs, and ICM from a misfire issue i was having and I'll definitely check but with everything almost brand new I don't think that it could be one of those things.

I was thinking the Idle air sensor or throttle position sensor for the weird start and high idle but would those also cause a misfire? Any other ideas?

have you changed tps on that? my pa i put everthing on it wires,plugs,gas filter and ended up being the tps(throttle position sensor) also take hose off throttle body and look in at the butter fly see if it's gummed up you can get cleaner at autozone just for cleaning throttle body's.

good luck.....

[hammerhankinson]

I haven't tried it yet, but that's what I was thinking it was and was hoping someone would say that as well on here. I'll give it a whirl, thanks!!!

[hammerhankinson]

Well it isn't the TPS. Any other ideas?

[Scrapper]

Originally Posted by hammerhankinson

Well it isn't the TPS. Any other ideas?

it still could be in coil pack even tho you replaced if you got them at autozone i'd have the pack checked if you can look at spark and see if it's blue or yellow? yellow not good also have you looked at your plugs and check the gap. i know you put alot in this by the way is check engine light on?

[enslow]

If your missfire is in cylinder 1, look for things specific for cylinder 1. Things like TPS will affect all cylinders, and would give a random missfire, and perhaps no code at all because you need consistent missfires in one cylinder to be recognized by the computer.

I'd check that plug/wire again. Check that the wires are properly seated with a good coating of dielectric grease. Get an inline plug tester. If you have consistent flashing of the tester, it's probably OK. If spark checks out good, next check out the injector. You may need to remove the injectors and get them cleaned.

[hammerhankinson]

Well here's the weird thing, I got up early to work on the car this morning, started it up to check the codes and it ran fine. So with a big smile on my face I took it for a small test run and it ran great. Then a couple hours later i go to leave and it's misfiring on cylinder 1 again (with the check engine light on). So I used a spark tester and I have spark between the coil pack and wire, and wire and plug but the spark did look yellow. So why is a yellow spark bad?

I was in a hurry so I haven't pulled the plug yet to check the gap or to see if it's corroded, but I did just change the plugs about 8 months ago.

I'm also thinking the injector but wouldn't I get an "injector malfunction" code if it wasn't working? Or is it just dirty because it seems to be clicking, and if so how can I clean them other than using the fuel injector additive for your gas which I've used about 6 months ago.

[hammerhankinson]

Well I had another issue pop up today that I thought had been cured after replacing the MAF and fuel pressure regulator, it wouldn't start this morning without pushing the gas to the floor. After getting it started the one time it starts just fine after that. I tested the spark at all the coil packs to see if it was just the one that was giving me my cylinder 1 misfire but I'm getting the same yellow looking spark from all the coils. I am officially at a total loss at what's causing this.

[Scrapper]

Originally Posted by hammerhankinson

Well I had another issue pop up today that I thought had been cured after replacing the MAF and fuel pressure regulator, it wouldn't start this morning without pushing the gas to the floor. After getting it started the one time it starts just fine after that. I tested the spark at all the coil packs to see if it was just the one that was giving me my cylinder 1 misfire but I'm getting the same yellow looking spark from all the coils. I am officially at a total loss at what's causing this.

now i'm wandering if it's the module under coilpack?

[hammerhankinson]

Originally Posted by Scrapper

now i'm wandering if it's the module under coilpack?

Yeah I was wondering the same thing, and since I just replaced it 8 months ago I think it should still be under warranty.

I'm also thinking it might be the crankshaft position sensor, any thoughts on that?

[hammerhankinson]

Switched spark plugs around to see if it would change the cylinder misfire and it still gives me a cylinder 1 misfire. Like I said before I have spark from all the coils but the spark is yellow, if I'm getting weak spark from the coils wouldn't I have issues with more than one cylinder?

Also is there a way to check the ICM? I moved out of state since I replaced the last one 8 months ago and I tried to take it in and swap it under the warranty but it's apparently a pain in the butt to do so since I moved so I want to test it first before going through the pain of having it swapped.

[HotZ28]

For national part stores, all you should need for an exchange (warranty replacement) is the phone number you used when you purchased the part, regardless of what state you currently live! Believe it or not (BION), last year we replaced all three coils on a customers car & one week later, two out of the three failed (all were made in Mexico)! Needless to say, we installed ACDelco and problem was solved.

[hammerhankinson]

Originally Posted by HotZ28

For national part stores, all you should need for an exchange (warranty replacement) is the phone number you used when you purchased the part, regardless of what state you currently live! Believe it or not (BION), last year we replaced all three coils on a customers car & one week later, two out of the three failed (all were made in Mexico)! Needless to say, we installed ACDelco and problem was solved.

Yeah that's kind of the pain in the ass part. Between the 3 or 4 stores I could have gone to (I worked on my car a lot and used different stores depending on if they had the part) and the 2 or 3 phone numbers I could have used I have to go through each phone number and see if the part is tied to the numbers. I already called one store and went through the process and I felt like such a douche. Needless to say I'll keep better track of this information but I took it for granted since I've never gone through this process before. But I was just posting to see if there were any way to test the ICM before calling other stores and annoying the crap out of the clerks again.

[Scrapper]

Originally Posted by hammerhankinson

Yeah I was wondering the same thing, and since I just replaced it 8 months ago I think it should still be under warranty.

I'm also thinking it might be the crankshaft position sensor, any thoughts on that?

i doubt it's cps if it's since the one misfire they all would or it wouldn't start at all if cps is real bad. i'm thinking coil pack or as i said module. sometimes you get a bad part so that coil was probably bad from the get go it just got worse. and you know about all our parts are made over sea's. if you get anything from autozone or advanced you need to write on back of your ticket because there ink disapears after awhile and if you get lifetime warenty they take it out of there computer so i always write on back my ticket what it's for or if it go's bad it's your fault if you don't do this.

[hammerhankinson]

Replaced plugs, wires, coils, ICM, fuel filter, and O2 sensor about 9 months ago from a misfire issue I couldn't locate (ended up being the ICM). A few months back I replaced the MAF, TPS, and IACV from a Random misfire and MAF low input issue, which it fixed. Now I have a Cylinder 1 misfire that I can't figure out.

Checked for spark and I'm getting spark from all coils, and to the cylinder 1 plug (i only checked that one plug/wire connection). Swapped plugs with cylinder 1 and 2 and still getting a cylinder 1 misfire code so it's not the plug. Pulled the ICM and had it checked and it tests fine. I did notice that the spark was yellow and not blue though, which I believe is a sign of a weak spark but I don't know how to problem solve that issue.

Going to have the coils checked today but I can't imagine all 3 new coils going bad at the same time (they all are giving off the same yellow spark yet I only have 1 cylinder misfire).

Ideas?