1990 GTR please help!

[J freeman1]

I just imported a skyline from japan into america a few weeks ago, now that I got everything legal and cleared it seems to not want to run for s***. It seems to flood itself out, the exhaust temperature light flashes the whole time, once I pull the fuel pump fuse and get her stArted it runs extremely rich and when I give light gas it stutters hard, idle shakes the whole car and it almost sounds like a slight knock at the same time. When the light comes off it runs perfect for about 20 minutes, and then once the light is back, so is the terrible running. Checked my cat, maf sensors, tps sensor, got new plugs and coil packs, no leaks in exhaust. has an aftermarket ecu that doesn't seem to display codes, so no help there. I am completely stumped and it's driving me completely insane. Please someone help, it would be really appreciated! Thanks

[AZhitman]

...and so it begins.

Welcome aboard, J. Who did you import it through? Sounds like they sold you a turd.

What engine management system is it using? How did you check the MAF / TPS?

[J freeman1]

...and so it begins.

Welcome aboard, J. Who did you import it through? Sounds like they sold you a turd.

What engine management system is it using? How did you check the MAF / TPS?

I bought the car from Jim expo.com. Yeah it seems like I got sold a turd but now it's a turd I have to fix haha. I checked both of those, the engine management system is an impul hi power

[GSX-R35]

Where are you located and are you running it on pump gas? That Japanese aftermarket ECM may be tuned for a higher octane rating than what you're running especially if you're on the West Coast with our weaksauce 91. I have to wonder if your car may be running rough and knocking because of the tune not liking US gas. Maybe try throwing in an octane booster and see if it makes any difference?

[AZhitman]

Those sound like pretty drastic symptoms for octane deficiency alone.

I'm thinking MAF or TPS, possibly CAS. Again, how did you ensure that they're doing their job?

I'd be tempted to swap in a stock ECU and see how it goes, then work up from there.

[GSX-R35]

Those sound like pretty drastic symptoms for octane deficiency alone.

That may be true but at the same time we're not talking about a stock modern NA 4-banger, it's a 25-year old twin turbo I6 with a '90s era aftermarket ECU that was almost certainly tuned for higher octane gas. Bad gas would be an easy thing to rule out and much cheaper than getting a new ECU right off the bat. Either way, I think most people would agree he shouldn't be running the car on straight US pump gas until he can get it retuned and fix whatever ends up being the cause.

[AZhitman]

Yeah, not knowing what kind of tune is on that ECU is a big no-no. Hell, he may have already done some damage.

[J freeman1]

Yeah, not knowing what kind of tune is on that ECU is a big no-no. Hell, he may have already done some damage.

Maybe but I don't think it's a tune because when the check light is not on the car runs.perfect, not too lean, not too rich, just nice and smooth. It seems electrical to me. Trying to find a maf at the moment

[J freeman1]

And now it won't even start. Was going to try and limp it into my local garage, and nothing. It fires occasionally, it started and ran on 3 cylinders for about 10 seconds. It just floods out and won't let itself start. Ever love something but also want to burn it to the ground? Thats how I feel right about now.

[AZhitman]

Until you figure out what's going on, continuing to fire it up is likely doing damage. You don't really have any way of knowing if it's running lean or rich (unless you have a wideband). Did you measure voltage from the MAF, TPS, and CAS?

We have a FSM right here on the site with a full troubleshooting progression. There's no reason to keep beating on it and expecting something to change.

[J freeman1]

Until you figure out what's going on, continuing to fire it up is likely doing damage. You don't really have any way of knowing if it's running lean or rich (unless you have a wideband). Did you measure voltage from the MAF, TPS, and CAS?

We have a FSM right here on the site with a full troubleshooting progression. There's no reason to keep beating on it and expecting something to change.

Yeah that's whY I stopped messing with it, I'm going to replace a few sensors and try again. I'm going to the o2 sensors, and if that doesn't work, I'll try the maf if that doesn't work I'm going to have a good cry

[J freeman1]

Well today I cleaned the he'll out of the o2 sensors, they were completely covered in carbon and the holes were almost caked over. I reinstalled them and the check engine light turned off but still won't start since its so flooded out, next up is to check if I fouled the plugs

[JDMEXPO-NY]

Did you fill up your tank shortly before this all started happening? I had that happen recently when I got some bad gas. Was supposed to be 93 octane but the car immediately started running like a** after getting half a tank. It runs super rich and stumbles until it warms up, then it runs decently but still not perfectly.

My guess is that you've basically coated everything in a layer of carbon and unburnt fuel. You've cleaned the o2 sensors, so next clean the maf and clean or replace the plugs. Put dry gas in the tank in case the station had water in their tank and never go to that gas station again. Putting seafoam in the tank may help clean things out as well. Do the seafoam before you clean everything though,

[J freeman1]

Literally everything is clean in the engine now. And still won't start, I've gone through literally everything, now I'm at my wits end. Used to love skylines but this car makes me want to drive it off a cliff.

[JDMEXPO-NY]

It sounds like it turns over, is it getting spark? Have you checked out this manual yet with a lot of troubleshooting info? http://www.skyline.se/dokument/R32_gtr_ ... manual.pdf If you find issues with the spark or coil packs, this might be a worthy investment (if they still stock it) http://www.buy-r.com/do-luck-direct-pow ... line-gt-r/

I hate to say it, but its a 25yr old fairly technical and complex car. It's going to have issues and need parts replaced and your local garage is probably not going to know what the heck to do with it. Do you have a local tuner/car club in your area that might be able to give you a hand and a second set of eyes? RB swaps into 240s are pretty common, maybe there's someone near you familiar with them.

[Wildtraveler]

If your CAS is out or not plugged in all of the way it will not start no matter how hard you want to try. Use a multimeter check wires if needed. Shoot run new wires strait to the ecu I've done that before just to see if it was wiring. There are some great break downs in this site. I had to buy a whole new harness to fix all of the issues with mine. Did you look for knock sensors? They are under the intake manifold. Mine ran like dookie until I figured that one out. I had to buy a small bore scope to find them they are in there pretty good! Run all new vac lines I'm sure that wouldn't hurt either. I was also missing a rear turbo exhaust wheel. Do you know if when it was running it made power? Maybe you have a leak after the maf maybe ic pipping or bad gasket on the intake side. Just some ideas hope it helps. Pm if you want more specifics on any one thing I listed. I'll try to help out.