runs like hocky

hello i have 94 2.4 l mmm has a bad misfire at idle almost kill the engine when drive hyw speeds truck runs great.
when i first bout the truck had a blown head gasket, milled head valve job done replaced head gasket intake gaskets exhaust gasket
coolant temp sensor. cleaned maf, ohm tested injectors all read 12.5-12.8, removed ecm didnt see no corrosion or blown capacitors. pulled plugs their white in color. I used to own a 93 mmm same motor when you engaauged the ac rpms would pick up on my new 94 that doesnt happen just runs even more rough im thinking its the idle speed motor but would that cause a misfire?. I like my little truck and want to run like my old 93

Before doing any tests establish when the problem is. Is it if you get it just off idle does it run ok? Or is it higher rpms that it clears up? I assume you changed plugs with head job. if it clears up off idle id lean towards dirty t-body or iac. If its higher rpm id lean to maybe a stuck fuel injector or check the dist cap for corrosion or for correct timing. These can be a pain to match up perfectly since the lines arent dead on compared to the book. Also with the head work were the lifters changed? They could collapse under idle due to low oil psi and build at higher rpm due to higher psi

White plugs? sounds very lean and burning hot. They should be a light tan color with a dark colored outer ring. Misfires could be a bad mixture adjustment also. Lean or rich the car will run rough. You don't want to run lean with all that new work done. You could burn a valve. Have you checked compression since the work was done and truck running?

Sorry I haven't replied back in so long and bring up an old thread but I think I've found the culprit. The intake manifold gasket is leaking coolant in the engine causing #2 misfire. When I installed the new gaskets I didn't apply silicone, my screw up. I ordered new gaskets, and lifters last week "I should have replaced these noisy lifters in the first place". Going to tear it back down and redo this tomorrow hope for better results.

*UPDATE*
Well got her put back together the other day with new lifters, intake gasket's fired back up still misfires like a @#%. Before myself blew a gasket I rented a compression tester, #1 150psi #2 150psi #3 and #4 dead 0psi. I suspected the head gasket blew in between 3,4 tore it back down and the new fel-pro gasket was still intact. At this point I was confused closely I examine the head on the work bench rotating the camshaft #3#4 exhaust valve's stay open at zero lash and the lash adjusters are maxed out. I disassembled the rocker arm assembly and laid a straight edge across the top of the exhaust valves 3,4 ex valves are 12mm higher than 1,2 I new right there was the problem the hole time. Ran back up to the store for a spring compressor removed all the valves and they measured the same height and no bends. So at this point the only thing left to check was the valve seats, OMG what valve seats they were nearly gone. Next morning I called the machinist that originally rebuilt the head asked him why didn't he replace the seats, he told me had to do a number on them with the resurfacer cause they were recessed. Asked him why didn't you just replace them he responded I don't install them. Never again will I let him work on my shitty. Dropped the head off today at a more advanced machine shop there going to replace the ex. seats and all valves. Now were can I find head bolts? don't want to use these stock a 3rd time.

I replaced my stock bolts with ARP and haven't looked back. Check out there site for a set for your motor.

http://arp-bolts.com/kits/Make.php?_...&_EngModelID=*

I've done alittle research on the 4g63 bolts and their 20mm shorter then the 120mm obsolete stock 4g64 head bolts. Now what about the 4g63 head studs will they tread all the way in the block, and have some room left for the washer and nut??

I can't speak from experience, but I found the thread below and it appears that several folks on the Galant forums are running the 4G63 bolts on their G64's. However, it also looks like they are running a G63 head on the G64 Block. Not sure if their is a difference in thickness of the head or not.

http://www.thegalantcenter.org/showt...ARP-Head-Studs

I'll do some additional digging and see what I can find.

Got it put back together with stock bolts the 3rd round. I may catch hell on here for doing so but the book plainly states if the bolts don't exceed 120mm reuse them :shrug:. I had no problem with the torque to yield they went in just dandy. Surprised napa had the seats and valves in stock the machine had me ready at 9:30 this morning $146 not bad. 150-160 psi across the board now very happy runs like a top. All I need to do now is fine tune with the distributor/and replace slippy clutch with all this new power! :thumbup:

those are not torque to yield, so you should be good to go. Glad to see you brought it bad to life!