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DroppedMitsu
08-21-2016, 03:00 PM
Ok I bought a non-running 1994 2.4l 4g64 about a year ago. Guy had replaced the engine and other stuff and couldnt get it to start/run. I bought it, change out the MPI relay as it wasnt getting spark and it starts up. It's running a bit rough and stuff so I check the timing, its off by a tooth or so so I fix that. So it starts but it still running rough/not wanting to stay running. I check the fuel filter and notice kinked lines, so I buy a new fuel filter and make a new fuel line. I figure this will fix it but no, still running rough. I check the codes and get a idle air control code, so I end up finding out the plug for it wasnt plugged in. Plug it in and no more code, but still not running correctly and wanting to die. I pull the throttle body off to clean it and notice it has a crack, find another at a junk yard after some time searching and figure this will fix it, no dice. I check the timing a bunch more times, base timing(cam sprocket,crank pulley, etc..) all fine, and hit it with the timing light and still dead on the money. Mess with the tps as maybe thats affecting it, throw on the original(looks newer) and adjust it to where its supposed to be, still bogging down and not running correctly. I finally decide to disconnect the maf and it starts idling and running pretty decently. This is where I'm stuck. I only get codes when I remove the maf plug, no codes other wise. The MAF has a rbuilt/remanufactured tag on it, and the ecu(which I have looked over 5+ times for cap issues,etc..) has either a rebuilt tag or is from the junkyard(cant remember which).

IT HAS THE EXACT SAME ISSUE AS BLINDXEYED WAS HAVING IN THIS THREAD, SOUNDS AND DOES THE EXACT SAME THING
http://www.mightyram50.net/vbulletin/showthread.php/80-More-of-a-RE-build-Thread

In short:
Will not stay running/when give it any gas it dies almost immed.

Have changed:
fuel filter(new)
MPI relay
TPS
Throttle body(old had a crack)

Have checked:
ECU(have looked over, caps/etc look fine[is either rebuilt or from junkyard,cant remember])
MAF(looks pretty new, has rebuilt sticker on it)

Can tell were replaced before I bought it:
Coil
Dist Cap
Rotor
Wires
Plugs
Coolant temp sensor
IAC/FIAV


I don't want to throw money at a MAF or ECU as they appear to be new and replaced not too long ago. At a loss about what to do/try next. If anyone has any suggestions it would be greatly appreciated.

pennyman1
08-21-2016, 04:32 PM
If it runs better without the MAF, I would start there first. There are a few swaps from eclispes I think that might work - check the threads for info on what works. The ECM could still be bad - stickers don't mean it is any good, unless it was just reconned.

camoit
08-21-2016, 08:43 PM
Where is LSRMike when you need his knowledge on these things. Shoot him a PM and get him on this.

finalfighter
08-21-2016, 09:00 PM
check the connections on the passenger side under the hood by the firewall. there could be some corrosion in there. i would also recommend checking the conditions of the wires going to the distributor and injectors.

finalfighter
08-21-2016, 09:05 PM
also if you are willing too i have a spare 94 ecm that i keep with me anywhere i go. if you want to pay for shipping so you can test to see if that's the issue i would not mind. if this does pan out to be the problem than you can keep it for junkyard price (PNP). just let me know. i will be making a couple rounds to some of the junkyards and will most likely find one to replace this one with. if its not the problem just ship it on back.

DroppedMitsu
08-23-2016, 07:12 AM
Thanks for the help/tips. I was figuring on trying another MAF first, then if not def an ECU.

Thank you finalfighter for the offer, I will grab a MAF this week sometime and try that, and if not I will get back to you on maybe borrowing that ECU if the MAF doesn't work out.

DroppedMitsu
10-22-2016, 12:00 PM
Figured it out this weekend. I didn't notice before but they had tried to "hack" or mod the maf sensor by removing restrictions and such and i guess the maf couldn't read correctly. Got another maf and all is well again.