98 Trans Am misfiring...
#21
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Alrighty... So here is what I have so far:
Today we drained out all the gas from the tank- it looked like apple juice. Then I scrubbed the tank with a brush and used a shop vac to get out all the shmeg out of the the tank and got it as clean as we could. Cleaned the sock on the fuel pump, then put it back in. I will probably still have to get a new pump but we figured we'd give it a go with the old pump after a good cleaning. Still ran like ****. It misfires and hesitates when I give it the gas.
So far I put in a new alternator, 2 front 02 sensors, plugs and wires...
Would the lack of fuel pressure from the pump cause it to behave like that?
A friend of mine who is a mechanic suggested that it could be a bad crank position sensor... anyone ever have any issues with a crank sensor? If so could that cause it to run like it does?
Today we drained out all the gas from the tank- it looked like apple juice. Then I scrubbed the tank with a brush and used a shop vac to get out all the shmeg out of the the tank and got it as clean as we could. Cleaned the sock on the fuel pump, then put it back in. I will probably still have to get a new pump but we figured we'd give it a go with the old pump after a good cleaning. Still ran like ****. It misfires and hesitates when I give it the gas.
So far I put in a new alternator, 2 front 02 sensors, plugs and wires...
Would the lack of fuel pressure from the pump cause it to behave like that?
A friend of mine who is a mechanic suggested that it could be a bad crank position sensor... anyone ever have any issues with a crank sensor? If so could that cause it to run like it does?
A bad crank sensor can cause misfires but usually when they go bad they don't partially go bad. It can happen though. Just depends on if you want to keep throwing parts at it..
Did you get the SES scanned? What were the codes?
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Haven't had a chance to wrench on this thing in a few days due to my busy work schedule and all the beers I consumed over Labor day weekend...
I don't have access to the classified section yet but I am selling my ATV- a 2003 Polaris Predator 500 if anyone is interested. Need the money to put into the TA. I have an ad on craigslist: http://providence.craigslist.org/mcy/3836126675.html
PM me for any additional info please. I need this thing gone asap.
I don't have access to the classified section yet but I am selling my ATV- a 2003 Polaris Predator 500 if anyone is interested. Need the money to put into the TA. I have an ad on craigslist: http://providence.craigslist.org/mcy/3836126675.html
PM me for any additional info please. I need this thing gone asap.
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prob not what you want to hear but mine ran like that and the push rods were bent. I spent alot of time and money doing what you are doing but ended up being push rods. hope it is not but that was not my case! It is worth pulling apart and checking out sound like you have as much time in it as it would have taken to do that.
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I hit rev limiter and car ran but real bad! It also went through big puddle air box was wet. Its not that bad to fix bottom end was still good I put cam in when I fixed. I agree find the problem before you start fixing things it would have saved me 600 bones! Awsome deal on car even if push rods are bent.
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Failing Crank Shaft Position sensors cause the engine to just shut off without warning. Then it will be very hard to start. Then it will start and run perfect. Then at the next stop light it will shut off again.
It doesn't cause misfires and hesitation.
A failing Cam Shaft Position sensor can cause misfires........
Get it scanned to see what those new 02 sensors are doing.
Yes, low fuel pressure will cause your issues.
Have you cleaned your MAF?
What gap did you use on the plugs? .050 is the best gap to use on any N/A LSx engine.
.
It doesn't cause misfires and hesitation.
A failing Cam Shaft Position sensor can cause misfires........
Get it scanned to see what those new 02 sensors are doing.
Yes, low fuel pressure will cause your issues.
Have you cleaned your MAF?
What gap did you use on the plugs? .050 is the best gap to use on any N/A LSx engine.
.
Last edited by LS6427; 05-30-2013 at 01:37 PM.
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Welp I put in a new fuel pump, but it is still running like ****. Going to scan it again tomorrow. I have a feeling there is a bent pushrod... so if pulling the codes doesn't turn up much I'll have to check them.
When you rev it up it has a spuddering backfire through the intake... also still idles poorly- seems like a misfire.
So far we have eliminated spark, fuel, cats, front o2's, voltage, checked all fuses and connections....
What else could it be?
When you rev it up it has a spuddering backfire through the intake... also still idles poorly- seems like a misfire.
So far we have eliminated spark, fuel, cats, front o2's, voltage, checked all fuses and connections....
What else could it be?
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Welp I put in a new fuel pump, but it is still running like ****. Going to scan it again tomorrow. I have a feeling there is a bent pushrod... so if pulling the codes doesn't turn up much I'll have to check them.
When you rev it up it has a spuddering backfire through the intake... also still idles poorly- seems like a misfire.
So far we have eliminated spark, fuel, cats, front o2's, voltage, checked all fuses and connections....
What else could it be?
When you rev it up it has a spuddering backfire through the intake... also still idles poorly- seems like a misfire.
So far we have eliminated spark, fuel, cats, front o2's, voltage, checked all fuses and connections....
What else could it be?
rockers, push rods, and valve springs.
did you perform a compression test?
or a leak down test?
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I have the day off tomorrow. So I plan on pulling the codes again, and if that turns up nothing, again, I will be checking out the push rods, lifters, etc. If that doesn't do it I'll probably either take a baseball bat to it, or sell it. I'll update the thread with whatever the outcome is. At this point I'm hoping it's a bent pushrod.
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I pulled the pushrods and wow they are bent to sh*t!
There is a link to pics of https://ls1tech.com/forums/members/b...ods-28922.html
I can't believe how bent they are.
Big thanks to 2BirdJosh- you were right my man.
Thanks to everyone else for the input, was a big help. Glad I joined LS1Tech.
If the link doesn't work just click on my profile and look at the album, and try not to laugh tio hard.
There is a link to pics of https://ls1tech.com/forums/members/b...ods-28922.html
I can't believe how bent they are.
Big thanks to 2BirdJosh- you were right my man.
Thanks to everyone else for the input, was a big help. Glad I joined LS1Tech.
If the link doesn't work just click on my profile and look at the album, and try not to laugh tio hard.
Last edited by BlackBirdLSOne; 06-07-2013 at 01:48 PM. Reason: typo
#37
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I pulled the pushrods and wow they are bent to sh*t!
There is a link to pics of https://ls1tech.com/forums/members/b...ods-28922.html
I can't believe how bent they are.
Big thanks to 2BirdJosh- you were right my man.
Thanks to everyone else for the input, was a big help. Glad I joined LS1Tech.
If the link doesn't work just click on my profile and look at the album, and try not to laugh tio hard.
There is a link to pics of https://ls1tech.com/forums/members/b...ods-28922.html
I can't believe how bent they are.
Big thanks to 2BirdJosh- you were right my man.
Thanks to everyone else for the input, was a big help. Glad I joined LS1Tech.
If the link doesn't work just click on my profile and look at the album, and try not to laugh tio hard.
![EEK !!](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_eek2.gif)
.
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Haha, yeah he was- The term "lifter rods" made me a little skeptical. But god damn were they bent. A few of them we had to take out with vice grips.
Anyways, after pulling the codes and seeing the cyl 2 misfire I pulled the valve cover and noticed I had a stuck valve. Gave the valve spring a few whacks with a rubber mallet to free it up and now it is running much better. Still not perfect- idle is a lt ittle choppy but once you get going in it, it runs perfectly fine. There is a lot of carbon build up in there, and I was going to seafoam it.
Anyone on here ever use it, or is there a better product out there to remove carbon?
Anyways, after pulling the codes and seeing the cyl 2 misfire I pulled the valve cover and noticed I had a stuck valve. Gave the valve spring a few whacks with a rubber mallet to free it up and now it is running much better. Still not perfect- idle is a lt ittle choppy but once you get going in it, it runs perfectly fine. There is a lot of carbon build up in there, and I was going to seafoam it.
Anyone on here ever use it, or is there a better product out there to remove carbon?
Last edited by BlackBirdLSOne; 06-09-2013 at 08:17 AM.