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1G Need some help diagnosing odd issue.

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dsm nuff said

10+ Year Contributor
91
1
Sep 14, 2009
Montoursville, Pennsylvania
I have litteralky posted all over the facebook groups, searched high and low on google, and had pretty knowledgeable DSMrs try and help, noone can seem to figure this out.
Car is a 94 Eagle Talon 6/4 combo. Heres a mod list.
Rebuilt 6 bolt head stock internals unknown brand adjustable cam gears.
Stock bottom end.
Brand new only idle time gates timing belt and water pump kit with oem timing belt tensioner.
Ebay tubular headers.
N/a throttle body with isc disconnected and coolant ports looped.
Ebay 20g turbo.
2g maf.
Full wire tuck and fusebox relocation.
Fic 550cc injectors
Walbro 255 fuel pump
Fuel lab 818 tank to rail fuel line with fuel lab fuel filter
Ss braided oil feed line from head.
90 ofh with exteranl oil cooler.
Greddy knock off bov
Fmic with short route hard piping.
Battery relocated to trunk with kill switch.
100a inline fuse in place of factory fuse block that goes to the positive battery terminal.
3 inch straight through turbo back exhaust.
Injen hard 2g intake pipe.
Torque solution drive shaft carrier bearing bushings.
Ss braided clutch line
Exedy stage 1 clutch
Removed bs belt.
Egr block off.
P/s, a/c, and emissions full delete.
Innovate lc-2 wideband

Think thats pretty much it, alot of that is irrelevant to the issue anyways.

Ok so im gunna try my best to describe this.
Car starts a little rough, sometimes you have to crank it for 30+ seconds unless it was just running. Once it starts it idles great around 875 rpms. Afr at idle is around 13.9. Car free revs fine, breaks up a tiny tiny bit every so often usually just when its cold and you try and go more than 1/2 throttle. It will hit antilag at 5k and timing retards like it should. Builds 15 lbs no problem right where i want it for now. Once you let off tho itll run a little crappy for a few seconds until the ecu evens it out. This i believe is because i havent found a way to recirculate the bov just yet because of the placement. Im working on it. So all is good, you put it in gear, give her gas and easeboff the clutch. Soon as the clutch is out it just goes full lean, bogs right down and wants to die. Its like an intercooler pipe ks completely missing. Takes forever to build up and speed and to get the rpms up. Its not even driveable. Even at wot it does it. It doesn't matter how much or little gas you give it. Now ive gone thru the patch harness, its perfect. Tried my evo ecu in a friends car, runs great. Scaled injectors, messed around with latencies, all of that. No change. Put my 450cc injectors in, scaled them, no change. Put the stock pump back in. Still nothing. Put the stock ecu in and still nothing. Tried 3 known good mafs, 3 sets of plugs, wires are brand new, tried 2 coil packs, 2 cam angle sensors, mechanical timing is perfect, ignition timing is perfect. It has 2 very very small boost leaks, one at bov flange and another at the tb seals i think. I cant find evidence even with soap and water that the tb seals leak, i can just hear the air. I cant feel it. So i ordered a vrsf fmic kit because my piping is all jacked, and the fmic is old and mangle but doesnt leak. I just wanna make sure thats no issue. Theres no vacuum leaks that i can tell and ive tried another stock fpr as well. I dont currently have an afpr but its in the works just gotta get the money together after ordering the vrsf kit. Now idk if im losing fuel pressure somewhere but theres no fuel leaks, the injector seals are all brand new and the o rings, and i made sure the fuel pump was not leaking inside the tank. Im lost. Very lost and so is everyine ive talked to. Ive checked everything i can think of. All the ground leads and all of that. So if youve got any ideasbplease throw them my way im willing to try anything at this point i need this thing going and j have too much money into this build for this type of crap to happen. Thanks in advance.
P.s. typed this on my phone so please excuse any grammar mistakes and i couldnt scroll back to add to the mod list i forgot to mention its got an evo 8 ecu, evo scan and ecu flash. And im still using the 1g knock sensor til i find an evo 8 knock sensor. Thank you.
 
How's your ecu coolant sensor? Try unplugging it and see if there is any difference. It should go into dump lots of gas in the engine mode. My car would always run really rich, it had the wrong temp sensor installed. My car is a 95 but I couldn't ever get the cel to shut off.. Always said engine never warm code.. Then I researched and found some 95 cars ecus still wanted to see the older style temp sensor..
 
It sounds as if you have multiple issues you need to resolve (some you seem to already be aware of). I would also start at the coolant temperature sensor to address your cold start issue.

Identifying the Coolant temp sensor the ECU is looking to for can be found in the diagram below (#5):


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Checking to ensure it is plugged in, or for corrosion would be the first step. The next step would be testing it. See the following link for testing:
http://www.dsmtuners.com/threads/1g-talon-idles-rough-after-its-warm.384352/#post-152357483
 
Sounds like a few issues possibly. Since the isc is removed it may run rough until it's warmed up not a big deal since you should warm a car up to begin with anyway. Your bov not being recirculated can cause a drop in idle on deceleration which you know. The diaphragm in those knockoff greddy bov are known for going bad. Have checked to see if your idle switch and tps are adjusted.what are your cam gears set up to has the engine been degreed, you can't always trust the marks on the gears.
 
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