my SR runs like crap!!!

[xs081]

89 s13 w/sr20det red topok . when i received motor i noticed that previous owner had tampered/adjusted cps(cam position sensor). now i have motor in car starts jus fine but getting black smoke out the tail when revved. i test drove it and its fine till warm up then bogs like hell. i reset timing at 15 btdc. but i couldnt get my timing light to work. i tried both ways, loop wire at bak of motor and sprk plg wire inbetween #1 coil and sprk plg, neither worked. i pulled #1 sprk plg out and it was wet and blk as hell. all others jus blk. i checked o2 and maf there fine. so all ican think of is either way too rich or sprk plgs are gone but i replaced sprk plgs w/ blitz iridiums. im now beyond my nologe of engine diagnostics. any help or recomondations would be greatly appreciated. thanks

[Cyberkreig]

you are either running to rich, or not getting combustion. Check each of your coilpacks for good spark. Re test your MAF.. I dont trust those things... other than that... check your FPR and injectors/injector Orings.

[Cyberkreig]

If a mod'll move this for you, you can probably get some more advice.

[DeltaSteve]

also, if your plugs are covered in oil, you may need new piston rings or a headgasket. do a compression check

[Cyberkreig]

it may not be oil, i suspect that it is unburnt fuel. Especialy if he has little power and black smoke from the exhaust.

[180sxsr2o]

I had simular problems with my friends Toyota Supra when we had pulled the motor to have some work done. I know that the supra and the sr share the same ignition system. Are problem went on for two days at 12 hours a day of diagnosis. We went to go replace the igniter to find out that it had a loose connection. Other than that I would switch the coilpacks and see if it does it on that cylinder still. I have alot of knowledge of the sr and simular motor's. That use the same type of component systems. The reason why it would run good cold is because it switches from a closed loop (cold) to an open loop (operating temp 160 deg. and above). Also mabey the last guy was playing with the ecu and messed it up. I have two good ecu's for that car if that is the problem........ GOOD LUCK MAN if you have any question please don't hesitate to ask.

[bigRy]

hey thanks for everyones insight. i'll go back and recheck everything again. if i fix the prob i'll let yall know what it was. thanks again

[bigRy]

oops i guess i have two screen names on this forum

[humpy012]

hey thanks for everyones insight. i'll go back and recheck everything again. if i fix the prob i'll let yall know what it was. thanks again

run a compression test while youre at it, it takes 10 minutes. Im sure you have already put a ton of time in it already, so you got nothing to lose

[bigRy]

i found out today my maf and cas isnt sending info to ecu so i have problems in the harness which doesnt suprise me cause when i got the motor the harness was cut in half 6 inches from the ecu plug. everything else is fine. comp is good, all cylinders firing no leak in i/c piping or vacuum lnes.