1998 s14 with Sr20det black top
 

Hey I’m new to this website and I was hoping some one could help me with my s14 black top.

I just got this car two weeks ago and I notice this issue it had. Every time I came to a complete stop my car would bog out/ cut off as well when I turn the car on if it’s cold it idles perfect, but once it start warming up to it’s normal temp rpms start to drop and if you floor it the car cuts off. Also the car has no power what so ever on first and second gear it takes it a while to build up speed.

I’ve tried changing the coolent sensor, changed spark plugs, messed with the tps, messed with the maf, checked for leaks idk what els to check...?

boost leaks, check leaking bypass,

Hey kingtal0n I’ve actually tried that as well and no leaks but some people have told me as well to check if I have the right ecu for my blacktop but I wouldn’t know where to lock up if I do have the right one

1. compression test
2. pressure test
3. timing test
whats the wideband say....




....4. get a wideband

Is the blow off valve recirculated?

No it’s not recirculated

Yeah that’s going to be my next step to get a wideband and if doesn’t work I’ll post the numbers it was making. Thanks

these engines are remarkably simple.

Fuel goes
maf -> ecu -> injectors

spark goes
cas -> ecu -> coils

The only places to really screw up here are
1. timing
2. maf related (boost / pressure leak or incorrect maf, placement, position, recirculation interference, all of that stuff)

and of course there is always
3. general misc. (wrong ecu/leaking injectors/wiring related/bad fuel pump/etc) but these are more apparent

Thanks I really appreciate it I’ll get working today and checking all of that out and see what I can find.

One last thing how can I find out what ecu is the correct one for my black top

1998 Notchtop with VTC Engine uses black "NA" ECU
1995-1996.5 uses red "WC" ECU
1996.5-1997 uses black "WC" ECU

iirc Both WC Ecu share a harness, but the NA ECU will NOT Plug into WC harness. So you can not possible have the wrong ECU since it wouldn't plug into the harness (apparently :D)

also make sure the maf is an adequate distance away from the turbo.

recirculate it, it messes up your maf readings. Thats probably why your car shuts off when you come to a stop. Try that first before you waste money, could solve your other problems.

Add to the list
Check the IACV - they can get clogged up with carbon residue.
Dismantle & clean and you should get a stable idle.

Check if the O2 sensor is still working this can affect idle quality when the car is warmed up.