98 Trans Am misfiring...
98 Trans Am misfiring... Okay- I just picked up this car over the weekend. It's a 98 TA, automatic with only 80K miles on it. The guy I bought it from didn't know anything about cars and his mechanic or neighbor (some bozo) told him the "lifter rods" may be bent. After that he pretty much parked it and it sat for a long time- maybe a year or so. A friend of mine assured me that it wasn't the case, so I lowballed this guy and got the car for $1100. Basically it's misfiring all on one bank. So far I replaced the front O2 sensors on both sides. Today I picked up a new alternator and battery and will be putting it in tomorrow, along with plugs (yay fun) and wires.
Any other suggestions about what could be going on with this car to cause that misfire?
Also it's got a quarter tank of sh*t gas in it, and I'd rather not have to drop the tank or drill a hole to drain it out- any additives (other than a can of premium gas) any of you guys can suggest would be appreciated.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
Any other suggestions about what could be going on with this car to cause that misfire?
Also it's got a quarter tank of sh*t gas in it, and I'd rather not have to drop the tank or drill a hole to drain it out- any additives (other than a can of premium gas) any of you guys can suggest would be appreciated.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
98 LS1 Misfiring on one bank Okay- I just picked up this car over the weekend. It's a 98 TA, automatic with only 80K miles on it. The guy I bought it from didn't know anything about cars and his mechanic or neighbor (some bozo) told him the "lifter rods" (lol) may be bent. After that he pretty much parked it and it sat for a long time- maybe a year or so. A friend of mine assured me that the motor wasn't shot (and it isn't), so I lowballed this guy and got the car for $1100.
Basically it's just misfiring all on one bank. So far I replaced the front O2 sensors on both sides. Today I picked up a new alternator and battery and will be putting it in tomorrow, along with plugs and wires.
Any other suggestions about what could be going on with this car to cause that misfire all on one bank?
Also it's got a quarter tank of sh*t gas in it, and I'd rather not have to drop the tank or drill a hole to drain it out- any additives (other than a can of premium gas) any of you guys can suggest would be appreciated.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
Basically it's just misfiring all on one bank. So far I replaced the front O2 sensors on both sides. Today I picked up a new alternator and battery and will be putting it in tomorrow, along with plugs and wires.
Any other suggestions about what could be going on with this car to cause that misfire all on one bank?
Also it's got a quarter tank of sh*t gas in it, and I'd rather not have to drop the tank or drill a hole to drain it out- any additives (other than a can of premium gas) any of you guys can suggest would be appreciated.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
Couple things here:
1. How do you know it is misfiring on one bank? Using a scanner?
2. If it is indeed misfiring one side, check the injector fuses under the hood for a quick test.
3. If those are fine then I would start checking for spark. Make sure you have good spark on each cylinder
4. If you have injector pulse and spark then I would really start looking at a clogged catalytic converter.
Hopefully one or more of those point you in the right direction. Good luck. Either way you stole that car.
1. How do you know it is misfiring on one bank? Using a scanner?
2. If it is indeed misfiring one side, check the injector fuses under the hood for a quick test.
3. If those are fine then I would start checking for spark. Make sure you have good spark on each cylinder
4. If you have injector pulse and spark then I would really start looking at a clogged catalytic converter.
Hopefully one or more of those point you in the right direction. Good luck. Either way you stole that car.
Also it's got a quarter tank of sh*t gas in it, and I'd rather not have to drop the tank or drill a hole to drain it out- any additives (other than a can of premium gas) any of you guys can suggest would be appreciated.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
I'll be putting up some pics of this project soon, but any input would be great.
Thanks.
misfiring on "one bank" is a crazy statment.
if it starts run the car, and see how it feels and sounds.
scan it for any codes.
jack it up, take off the fuel filter and run a hose off one end into
a gas can.
power up the fuel pump and run the tank dry.
check all wiring and fuse boxes for mouse nests and anything chewed up.
nice score
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Don't you mean I'll be working on it tomorrow, noob. nice rip off my tag, and welcome to tech. I'm the friend who found it for him btw. the "misfire on one bank" is what the last owner's neighbor told him when scanned it and that the "lifter rods" were bent. but the guy said it did still run just rough. and that's where it's at now, after sitting for a couple years at least. found one cut, electrical taped spark plug wire, replaced that and the front 02's so far. helped but still runs rough. I can get a scanner tomorrow to see what the actual codes are. alternator is seized and was running on a dying battery showing around 8 volts on the dash. we'll see where we get with it tomorrow.
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Ya the scanner can be pretty useless when trackin down misfires. The batt being at 8v could also cause those issues too. If the car still has a miss after the new charging system I would swap the coil banks and see if it runs different. Then with a pair of rubber gloves individually pull of a plug wire one at a time and see of the engine pitch changes. When you find one that doesn't do anything unplugged you found the dead cyl
PCM to Engine ground wire could be loose.
When mine came loose Bank 2 was misfiring badly. Bank 1 was perfect. Then after a little while Bank 2 completely stopped firing on all 4 cylinders. I knew this because all 4 exhaust pipes off the head were dead cold while it was idling and struggling to stay running. But it was a smooth idle....which is wired.
A guy came over and grabbed the bundle of wires that comes directly out of the PCM and he moved them side to side and back and forth. As he did that the Bank 2 would start firing normally and running perfect. Then bad again,
He dug into that wiring harness to find that my PCM to Engine ground wire had shorted out and was barely making contact anymore. It was like burnt through the wire almost. He replied a new wire onto it and bolted it down to one of my valley cover bolts to ground it. Instead of dicking Round with connecting it to the back of the passengers side head like normal. Started it up and it was good as new.
Also, reach back behind the passengers side head....see if either of the two ground wire bolts are loose.
.
When mine came loose Bank 2 was misfiring badly. Bank 1 was perfect. Then after a little while Bank 2 completely stopped firing on all 4 cylinders. I knew this because all 4 exhaust pipes off the head were dead cold while it was idling and struggling to stay running. But it was a smooth idle....which is wired.
A guy came over and grabbed the bundle of wires that comes directly out of the PCM and he moved them side to side and back and forth. As he did that the Bank 2 would start firing normally and running perfect. Then bad again,
He dug into that wiring harness to find that my PCM to Engine ground wire had shorted out and was barely making contact anymore. It was like burnt through the wire almost. He replied a new wire onto it and bolted it down to one of my valley cover bolts to ground it. Instead of dicking Round with connecting it to the back of the passengers side head like normal. Started it up and it was good as new.
Also, reach back behind the passengers side head....see if either of the two ground wire bolts are loose.
.
Welp here is where it stands-
Put in a new alternator and battery, 2 new front O2 senseors, checked the PCM wire, new plugs and wires... and it runs like sh*t still. Misfiring like a bastard and won't rev up. Throttle response is real laggy. Tried to drive it 50 ft next door to scan it but the guy wasn't there, ot stalled a bunch of times and couldn't rev up to get beyond first gear. Soooo...
Any suggestions? Btw I treated the gas but didn't add any
Seems to be the same symptoms as when the guy I bought it from parked it (from what he described)
Put in a new alternator and battery, 2 new front O2 senseors, checked the PCM wire, new plugs and wires... and it runs like sh*t still. Misfiring like a bastard and won't rev up. Throttle response is real laggy. Tried to drive it 50 ft next door to scan it but the guy wasn't there, ot stalled a bunch of times and couldn't rev up to get beyond first gear. Soooo...
Any suggestions? Btw I treated the gas but didn't add any
Seems to be the same symptoms as when the guy I bought it from parked it (from what he described)
check your fuel pressure and see if anyone with a f-body
will let you swap ECMs to make sure thats not a issue.
does this car still have factory cats?
if so...go for a ride with the O2s out to see if
excessive back pressure is a issue.
will let you swap ECMs to make sure thats not a issue.
does this car still have factory cats?
if so...go for a ride with the O2s out to see if
excessive back pressure is a issue.
My friends with LS1's both have cammed and built cars, so that is not an option. This car is bone stock. Hopefully I can have it scanned soon but I would like to try and eliminate anything that I can for free at the moment, this is a real budget project. Hoping to at least figure out what the hell is going on with this thing without spending a bunch of money. Any other suggestions would be much appreciated though. I will look into everything and let you guys know how it turns out. Worst case I'll part it out or sell it.
if it is as bad as you make it sound, you should be able to tell
right away if its same or better.
...unless its BigStuff 3 or FAST LSX stand alones.
I'll have her scanned tomorrow and pull the codes. Try and narrow it down from there. I'll post my findings tomorrow. Thanks everyone for the imput, every little bit helps. I'm dying to get this thing on the road and tear it up. I'm glad I joined LS1 Tech, you guys have been very helpful thus far and I'm sure with some input from you guys and a little work I'll have it running right. Wish me luck. Thanks. More posts and pics to come- I'll keep you updated.
Had it checked out and looks like it's the fuel pump. Not to mention the gas in it is absolute ****. It is only putting out about half the pressure it is supposed to. The guy I got it from had mentioned that he had the fuel pump replaced recently before it started running like **** and he parked it. Was going to do the "trap door" install so that we don't have to drop the whole rear end and tank, and as it turns out- the trap door is already there. Plan is to drain out the **** gas with the old fuel pump, install a new one and dump some fresh gas in, along with some injector cleaner. Hopefully this will solve my problems.
Will let you know results.
Will let you know results.
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?