soneencris

I have a 92 sc400 that will not rev past 4000rpm. There is no check engine light and other than this, the car drives fine. It idles good, starts right up, and drives smoothly. I have searched and though I have found people with similar problems, no one has an answer. I have checked the AFM, TPS, and fuel pump. All of those things are working as they should. If anybody could point me in the right direction, that would be great.

Thanks,
Chaco

Relapser

is your maf sensor plugged in

and you cleaned your MAF sensor recently

try resetting the ecu again

xo

trufanatic

coil packs, change em. MAF doesnt really go bad on these cars.

soneencris

Changed the Maf, so I know that is not the problem, and I did reset the ECU. I have not changed the coil packs, but is there a way to see which one or ones it might be? Also are you talking about the ignition coil pack, or the igniter?

1jzchris

it could be that your ECU is going back.try another ecu if you can.

soneencris

Ok, replaced both ignition coil packs, and didn't fix the problem. Changing the ECU is on my list, but are there any other suggestions?

1jzchris

how did you check the fuel pump ?...........maybe pull the spark plugs and see how they are burning.Rich or lean

soneencris

Brigded fb with b+ or something like that. I have been haveing this problem for a bit, I though it might be transmission related. I did a w58 swap, but I still have the problem.

eddie26

iTrader: (4)

has your cluster been swapped out? i know if you put an sc300 cluster in, the tach will read a max of 4k rpm. probably not the issue, but i'm gunna throw it out there anyways

soneencris

Yeah, it still has the sc400 cluster in it. Is it possible for the cluster to be bad and cause low rev limits? Sorry if this is a dumb question.

ashtray

iTrader: (12)

try a new maf. If not that restart the ecu. if not that then maybe o2 sensors? Just throwing in my 2 cents man. Good luck.

1jzchris

Did you check the ECU yet?

soneencris

Yeah, reset it, but no change. I bought an ECU from a member. Just waiting for it to get here. If that is not the problem, I think it would have to be a bad connection somewhere. I read on another forum, that it might be a low battery. Is that possible?

soneencris

Just replaced the AFM. I had a CEL for an o2 sensor, but I still had the problem after I changed it(the one under the driverside). CEL went away. This is super frustating, I have a v8 5 speed I cannot take advantage of.

Rommel

i have the same problem like yours with my sc400. i have not change my 02 sensor yet. my cats are all brand new, new tps. i guess it's the 02 sensor.