Got a ke-38 with a 4afe conversion with a custom vj20 turbo setup.

 

Decided to service it a few weeks ago (oil change, plugs, fuel and oil filter, leads, dis cap etc) and I'm not sure if its related but its been running like crap ever since. I blew an oil seal in my turbo at the same time so i swapped the turbo for a newer but the same model turbo. changed all that and thought it was my plugs all along. Tried iridium plugs at .8 gap with a heat range of 5, it runs good until the turbo spools. Tried standard ngk with a .8 gap and a 7 heat range, same thing. then i got tried ngk racing iritop 7 and it runs rough but will boost to 20+ pounds but only with a tiny bit of accelerator. If i accelerate too hard it will just back fire and carry on like an old tractor.

 

Also i blew a 30A fuseable like from the ecu harness (i think) and i replaced that at the time of my service. I have a haltech aftermarket ems, not too sure if there is a stock ecu, and maybe it has crapped itself. Or if the haltech reset itself and i need to dyno it again. It seems like its receiving too much fuel and not burning it, causing it to flood and back fire.

 

I also think it maybe the fuel regulator from the aftermarket fuel pump too. Need some advice badly. I could replace everything before i have any success.

Edited May 23, 200818 yr by quickvan

Wow.. next time break everything down into neat paragraphs that hurt my head.

 

What fuel pressure are you running? try get a gauge and see whats happening when it start breaking down.

 

Did u keep the old dizzy cap? maybe change it over quickly see if it helps.

 

Change both the cap n button?

 

Is your fuel filter on the right way?

sorry wasnt keen on english at school.

 

Changed the dizzy cap, cos the stock one came with the leads attached to it. not the rotor button but. fuel filter was fitted correctly, and i have a gauge on the fuel regulator but it doesn't seem to work. it never has worked since i brought the car.

 

might cruise down to repco and grab a rotor button and try that??? hope the coil in the dizzy hasnt shat itself.

 

cheers anyway bro.

Could be an air leak between the turbo and head somewhere. I'd also be having a look at the hose to the map sensor. My old 4age had something similar and it was a hole in the hose to the map sensor. Idling was fine but when i gave it a bit it'd run rough etc

Could be an air leak between the turbo and head somewhere. I'd also be having a look at the hose to the map sensor. My old 4age had something similar and it was a hole in the hose to the map sensor. Idling was fine but when i gave it a bit it'd run rough etc

 

Where is the map sensor? i don't have a workshop manual yet. sounds possible but, i thought it may possibly be a vaccume leak or something.

What it looks like

Usually bolted to the firewall close to the manifold.

cheers for the pic bro, just checked it out seems to be in good condition, is there a fuse inside it? maybe that has gone. does that go to the ecu?

Your boost is blowing out the spark. Try some normal standard champion plugs and close the gap up more. You may need a stronger ignition system if it persist.

Have you got the wastegate hooked up? 20psi at part throttle sounds rather obscene to say the least! Sounds like its free boosting and running lean and/or blowing out the spark at the same time like Des said. The backfiring definitely sounds like a lean mixture to me.

Have you got the wastegate hooked up? 20psi at part throttle sounds rather obscene to say the least! Sounds like its free boosting and running lean and/or blowing out the spark at the same time like Des said. The backfiring definitely sounds like a lean mixture to me.

 

Yeah its an external wastegate, on the biggest angle i could get. And it boosts to 10 and builds up to 20psi with a few coughs and farts up the revs. Mmm lean hey, so i prob need a dyno then to fix that. It's still blows out a bit of soot on cold starts so it shouldn't be too lean.

Guess its a trip down to the dyno for the old girl then.

 

Thanks for ur help

Black smoke on a cold start is ok just so long as its not in exessive amounts. Change plugs and close up the gap before you send it down for a dyno tune and see what happens.

 

$10 on cheap plugs is better than hundreds spent on a dyno.

i see you have your car for sale.

 

can i ask how long you have owned it for?