The car in question is a 98 Sunfire GT. Long story short, car is really sluggish, no acceleration so I had the fuel filter replaced. It drives fine for 5 minutes, and then throws a P0301, or cylinder one misfire. Idle is still very steady around 1100 rpm, and the car is driveable, but you can easily tell its only on 3 cylinders. So far this is what we have done:
1- New plugs - no change
2- New plug boots - no change
3- new coils - no change
4- new (used) ignition control module - Cylinder was firing, and missing a bit, but returned to missing all the time almost right away.
5- new injector on cylinder 1- No change
Compression is good, providing the first cylinder is the one on the right of the block, by the control module. I am totally lost to what it could be....Ecm issue maybe? Could I have dumb luck and have two modules that are screwed in the exact same way? Somebody give me some insight please before I have to take this in to the dealer.
Maybe a vacum leak. Check the hose on the map sensor.
FU Tuning
Cylinder 1 is closest to the timing.
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4 Cams...32 Valves...5 Liters...This Could Get Fun!
i thought cylinder one was by the timing housing, what is the compression of the cylinder over there?
Jeez....3 guys were sure as $hit cyl 1 was on the other end. We didn't test any other cylinder for compression, and now it sounds like the wrong injector was changed. If infact a valve was stuck, why would it release after we change the ignition module and then freeze up again. This is weird.
per haynes manual #1 cylinder is on the passenger side of the motor by the timing housing, we all know the haynes manual isn't the best. from the driver seat yest it would be on the right side, but from the front where you would be standing to do the work it will be on the left right next to the timing housing. just trying to help, not trying to be a smart a$$
No, I posted for advice, and this was a huge oversight on my behalf. I'll check the compression today. What is the likelyhood of a clogged injector? Is it worth it to swap for a new one?
When checking compression, you should check all cylinders and compare the numbers. You may get something like 140-180-185-175. If only the first cylinder was checked, you may think it is good but compared to the other three, it is not.
you replaced the coils, but did you replace the coil housing?
Sir Tipsy
I actually had a friend suggest replacing the housing. Doing that, and compression testing all the cylinders tomorrow. If I can't figure anything out after that its going into the dealership.
Sir Tipsy wrote:you replaced the coils, but did you replace the coil housing?
Never understood this. I have never replaced this on any of my 2.4's I have owned.
FU Tuning
housing is a suggestion..they are prone to going bad
you've already replaced almost everything in the ignition system. did you check for spark before you started replacing it though? do you have a noid light that you can check for injector pulse on the number 1 cylinder with? number 1 cylinder is on the belt side just like on v engines number 1 is the cylinder closest to the belt (since the cylinders aren't directly across from each other) you're obviously getting pressure at the fuel rail since the other cylinders are firing. is a P0301 the only code you had? try testing the injector somehow to make sure it's working or at least getting power (even if you do something like pull the rail off the motor, put a 20oz soda bottle around each injector and crank the motor). if it's a fuel issue it sounds like something right at the injector and not a fuel pump or filter or fpr since it's not affecting anything but cylinder 1. definitely check the compression on all cylinders and compare them, try dumping some fuel system cleaner in the gas tank (granted it's not the best way to really clean out the system it might give you a clue on what the problem is if it makes a difference) and then let us know what you find out. there's no reason to go to the dealer for this. with all the new things you've put on it sounds like you should have good spark and since you said the fuel filter helped for a few minutes that would push me more to believe it a fuel issue over a compression issue. good luck man, let us know how it turns out.
How do I test spark in this car? Is there a specific tool? I really doubt a fuel problem, as when it starts cold, the exhaust smells like there is a lot of unburnt fuel in it, and as it warms, it smokes a bit, then just smells funny when the exhaust is hot enough to burn the fuel. I know I should have tested for spark right away, but I'm unaware of the procedure on these cars. Somebody enlighten me please. I had an evap code as well for the longest time p0440 I believe? I tried a new gas cap, and just clear it whenever it pops up.
I have seen exhaust valves misshape. I bet your exhaust valve or both on cylinder 1 are jacked.
normall to test spark you just pull a plug wire (or boot in this case), stick a screwdriver in it and hold it near a good ground while the car is being cranked. there is a specific tool for this, looks like a spark plug, but it's not. anyway, you should see a nice white/blue spark if it's good.
as for the P0440, you can get an evap leak from a LOT more places than just a gas cap. i've replaced many hoses and canisters because of evap leaks. good luck finding them though. a lot of times we need to use a smoke machine at work.
ITS FIXED! I tested compression on the cylinder, and it was perfect, but the spark plug looked brand new, as it had never fired once. So the coilpack housing was the last thing I could replace before swapping injectors, and it was the problem! A $5 piece of @!#$ty plastic makes or breaks the engine. Stupid GM. Thanks for all the help guys!
glad to hear it's fixed! sucks you went through and replaced as much as you did before finding the issue though.
coil pack housing?? I had the same problem, changed the housing ( plastic part under the IDI cover ) and solved my problem
If at first you don't succeed, destroy all evidence you tried!
glad to hear that solved the problem.
Sir Tipsy
sykeeok wrote:glad to hear it's fixed! sucks you went through and replaced as much as you did before finding the issue though.
A good friend had it all sitting around, so it cost me nothing except my time. I did get the plugs and the fuel filter replaced when it first started happening, and I DID pay a shop to do it, as I had no time that day, but that only cost me about $140, so I can write it off to regular maintenance.
Lol i went through the same @!#$ as you and changed everything you changed and ya it was the white coil housing but i had to replace mine like 2 or 3 times because it kept cracking due to it getting too hot. The problem was the water pump was bad so the engine was overheating.man i hope i never have to go through that @!#$ again!
Quote:
housing is a suggestion..they are prone to going bad
Quote:
So the coilpack housing was the last thing I could replace before swapping injectors, and it was the problem!
thats right! i was the only one who called it! ..your very welcome and i accept tips
I think it was Primative Fears friend, Sir Tipsy then scott!-------
PrimitiveFears-----------I actually had a friend suggest replacing the housing.---Sunday, November 18, 2007 10:01 PM
Sir Tipsy----you replaced the coils, but did you replace the coil housing?Sunday,-- November 18, 2007 10:22 AM
scott(section8cav)----housing is a suggestion..they are prone to going bad-----Sunday, November 18, 2007 11:46 PM
The main thing is, it was fixed.
Amazing that a supposed advance in technology can cause so many problems.
Alont
damn..i was soo close..oh well
glad he got it fixed ..those damn housings are a pain
