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04 gtp cylinder #3 missfire

k got a question for all of ya. I got a total estimate for 2 dif ways of doin this. I can get a total new rebuilt engine from jasper 3 yr warranty, new water pump, thermostat, and hes gonna fix tranny, and the front control arm bushings are bad gonna fix theminstalled all fluids newfor 4,000... or gonna do a leak down test on it to find out exactly what is wrong with whta i have, if its is the valves redo the heads, new water pump termostat and whatever other pulleys feel bad if ne, fix tranny, and control arms for no more than 2,500 he said thats the most all that would cost. Wonderin which route to go here, do i do a complete top rebuild and leave the bottom with 122,000 miles and chance it that nothin else is wrong down there, or do i just buck up and spend the extra 1,500 and get everything new with a warranty and no worries?????? Just want some opinions please..
 


go rent a scope from a auto parts store, or build one, youtube shows you how to. and take the plug out and look at the piston. if its got chips, get another engine.

for all that money, you could buy everything from engine lift to jack and stands and all the tools and another engine, and still have rent money next month. 4 grand id choke the guy first lol then laugh in his face.
 
well the engine is 2,700 alone, plus water pump, upper gaskets, fix tranny, and control arms, hes only charging 500 for all labor. just looked at a guys question in noob section he is havin same issue i am, and had heads redone, and tune up ecm tested,switched coils,and wires. He is still havin the problem its missing and low on compression. So now not sure what to do if i stick all that into it, fire a new engine up and its missing i will prob have 2 go to the nut house!! So now im at a total loss for what i should do this other guy has done what i was about to do and what i have already done????????
 
if you peek at the piston, you'll know what way to go for sure.

id be looking for a used engine, but thats me. these engines really do last a long time if taken care of. hell mines got 226,000 and it fires up with 1/2 a turn of the engine every time.
 
ya i no they run forever if taken care of with a used one you dont know how it was taken care of, and all of the ones i saw that i would be interested in were 1,700-2,000 so for a few hundred more i get a new one with 3 yr warranty. But now like i saidnot sure what to do, this guy had his heads redone, im sure they would have at least loooked at the pistons before they put it together, and he is still havin the issue. Missin on 3 and low compression on 5 mine is on 3 and 4 so a little dif, but pretty much the same. I will see if he has a camera or whatever to stick in there and take a peek, but thinkin about the leak down test, but is that gonna nail it down to the exact problem? After readin that guys post i am really nervous that were not lookin in the right place, would mass airflow cause this? someone said maybe.. or vaccum lines, shouldnt cause loss in compession though right??
 


I can almost assure you there is a chipped piston in that block of yours.

To save yourself some major coin, I really suggest you find a scrap yard L26 normally aspirated engine for about $500 and put your L32 goods on top of it. Lucerne, regal, grand prix, bonneville, Monte carlo, etc... There are tons out there.

You can do the full gasket needs on that for about $250 including heads, and you can then pay the guy $500 to remove your old and put this in. Heck, buy the gaskets from ZZP, drop off the engine for your mechanic and he will do it for you...for a mint less than you will pay for a rebuilt block.

Flush the valley while the block is apart, paint it if you like...and make it your own. It is going into a Comp G, and you have already invested alot in that car...and will likely hold onto it for a while. Wouldn't you like to do a personalization under your hood for the same price as a toss in rebuild that looks stock? Enjoy owning that GP...
 
Ya my dad and i are gonna do another compression test and a leak down this wknd. Just to try and find out what it is for sure. I got on it kinda hard tonight, and it seemed like the tranny slipped a little going into second, so not sure what to think about that now either. he said he thought it shifted kinda funny, but i dont really beat on it much if at all, but now wonderin if i just get that rebuilt also since its prob gonna come out, and he is gonna be takin some of it apart ne way to fix that clunk it there??
 
ok guys, now figure this one out. My dad and i did some checking on our own yesterday, and this is what we found. Compression on the 2 cylinders that were supposed to be low which was 3 and 4 was 145, so that is fine so no engine problems. Not sure how the shop figured it was low, We checked it four times had same result each time. checked ecm, coils, plugs and wires. ALL ARE WORKING fine and firing every time. So how is it that the computer shows a miss on 3 and can clearly hear a miss and feel it, and one shop says im low on compression when all checks out good??????????????? any ideas on this?????? What else could it be??????
 


do any of the switching coils, spark plugs and the plug wire around to see if it follows yet? all free and easy to do.

another misfire thread the guy found the plug cracked, check them over closely.

keep in mind cly 3 is in a heat sandwich. pron to chipping.
 
not sure how to trust any shop anymore have taken it to 3 diff. ones , and all said it was certain things, and when iget it back and check it out for myself there is never anyhting wrong with what they say it is. I mean how can you tell someone that there compression is low in 2 cylinders, and they both checked out fine. Is there anyway the mass air flow could have anything to do with this, we unplugged it also yesterday and it seemed like it went from hearing it come out the exhaust from 10 ft away to having to kneel down right nxt to it to hear it. Is that even possible??
 
I didnt do ne switching of wires or plugs, but the dealer said they did that. So who knows prob gotta do that myself too.. So i need a computer to notice if it follows the plug or wire so dors a place let u use one or how do i do that? or do i have to take it in and tell them to do it?
 
dont think the maf can cause misfires.

but a bad plug wire, plug or coil or icm can. or a chipped piston. move each part one at a time, swap the wire, if it dont move the mis, then do the plug, if it still dont move, then swap coil packs around.

coils can crack, icm's go bad, wires get f ed up to the icm. could even be a injector. you can swap them around too. or injector wire.

shops just want your money, if they do work and it dont fix it, to bad, sorry lets try this they will tell you, means they are not 100% sure with out playing with it at your cost. some shops will just keep tossing parts at a problem, even if it dont need it. but yet you'll be charged for the part. i hate shops myself.
 
yes i do to now ya thats all they say start here or try this. Then when i do it myself and ask them for a refund of the money i stuck into it the excuse is. We didnt do the work so we cant refund it!!!!!!!!!! what a bunch of BS......
 


my neighbor has a good one was about 500 bucks, but doesnt show each cylinder and how its runnin, just says cyl missfire. So must need a better one than that, and thats alot to spend. If i need one that bad i will get rid of the car i just need a dependable daily driver not all these headaches, im hoping to get this fixed and b done with it for a very long time..
 
the code would come up as p0303, (for cyl 3) each piston is labeled so you know what cyl has the misfire p0301, p0302 see what i mean.

if its getting a p0300 it means random misfires, aka all over the place.

his 500 dollar scanner would show that. it may not show live data tho. so ask him for the code that it pulled up.
 
I am amazed you are still having a problem, and have not moved wires/coils around yourself yet. Fack the shop man. Use a couple tools and do this yourself in 5 minutes.

Piston could still be chipped, so visually check that. Also important to check for cracked plug as mentioned. Swap wires and see if you move the problem. Are all the wires connecting good on the top of the coils? When coils get old/rusty, the contact points are not so good up top.

Even if you don't have a code reader...swap them anyways. You never know when you might find a bad contact and fix it yourself without the reader even being necessary.
 
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