[bigcraig987]

I just finished up the job of replacing the LIM gasket and when I started the engine the RPMs surged to about 1900ish and slowly fell to about 1100 and had periodic misfire. I turned it off, waited a few minutes and tried again with the same results. I didn't let the car run for too long, no more than 20 sec each time because I didn't want to hurt the motor. The car had been sitting for about 7 weeks because my college has class in the summer and just hadnt had a chance to finish it up until I got this long weekend. Could it just be old gas that started to break down in combination with idle relearn or did I mess someting up along the way? I labeled the plug wires when I took them out so they should be in the correct placement and I used the vacum line diagram to make sure I didn't miss anything. Any ideas will be helpful, I will put some fresh gas in tomorrow and try again but please post any other things that you think it could be.

 

[34blazer]

you may have left a vac line off or knocked it off. sounds like a vac leak. try checking all vac connections

 

[SuperDave]

are you sure you put the pushrods in right? the Exhaust ones are longer than the intake.

 

[bigcraig987]

i am sure i got the pushrods right, set them out in the way the came out to make sure, only lossened the rocker just enough to get the pushrod out so that they would just barely fit back in as another check, and the wear spots from the guides all lined up properly, ill double check the vacum lines behind the intake plenum, if one came loose it probably would be there when I had to fiddle with that bracket to get the egr tube on the proper side of throttle body cables, thanks for the ideas, ill let you know how it turns out

 

[bigcraig987]

i checked the vac lines and they all seemed to be on there good, put a little over 4 gallons of premium in it and still the same thing. I noticed the misfire does not start until after the rpms fall after the startup surge I am not sure if that gives anyone any ideas but I really just don't know what to make of this one, I replaced all the gaskets on my way back up (LIM to UIM, UIM to TB UIM to EGR) so I dont think that any of them are leaking so any ideas will be appreciated.

 

[SuperDave]

did you check the injector plugs, harness and injectors? maybe a pinched wire or something...

 

[bigcraig987]

I will add that to the things to check. I am going to grab my friend to have a listen and see if we can figure it out once he gets back from New York probably tomorrow, keep the ideas coming so that I only have to tear stuff down one more time if I have to.

 

[barrok69]

its probly burning off some coolant and other crap as well... so let it run for a bit.

 

[bigcraig987]

I let it run for a bit and pulled the plugs so I could see if certain cylinders were behaving differently. These were new plugs and have only but run at idle maybe a few minutes. Most have a fair amount of soot as you can see but cylinder 3 has very little and cylinder 6 has little soot but a little bit of the orange color like when they start to wear. Any ideas of what to make of this let me know. Is it possible that this all could be due to a couple of bad plugs and or plug wires. I think I will pull the wires and check the resistance so if anybody knows what it should be let me know that as well. Any ideas will be useful as I am going to need this running soon since winter and the snow season is coming up soon here.

 

[bigcraig987]

Finally found my multimeter and measured the wires, wire for #6 was bad giving me intermittent readings between 350 kilo ohms up to 1.3 mega ohms then rest on the front bank were 4.33 kilo ohms and 3.08 kilo ohms and the rear bank were between 11.35 and 13 kilo ohms. While I am at it is there a simple way to check the coil packs while I have the wires off just to eliminate them too in case new wires don't cure it.