new SR20DET swap running bad

[lightningph]

I've got a Redtop in an 89 S13. The ECU is throwing a MAF sensor error. I replaced it and it is still not running right.
I mesured the voltage from the MAF sensor at the ECU to be
1.3V @ 800 RPM
1.54 @ 1500
2.4 @ about 3000 (see below as to why it is about)
These values seem close enought to the specs that I think there is something else wrong. I have it wired up where
A=12V power
B= signal ground
C=signal
It idles at about 800RPM even after it warms up, but dips to 400 breafly after revving it. Before it gets warm, ideling around 2k RPM if you give it gas it bogs acting like it is going to stall before reving. It cannot be held at an RPM either revs or drops to idle. It is like an on and off switch. I can tell the fuel mix is supper rich by the smell.
I have a O2 meter that reads rich and then goes lean before going blank for a while before reading rich again. Durring this time the car will idle with no indication there was any change. I may have a bad O2 sensor but unplugging it does not change anything.
Could the ECU be bad? Is there anything else it could be? :hammer:
Thanks for any help!

[silverarrow27]

Still sounds like a maf related problem to me. I assume your wires when rewiring your maf plug, it was color to color match? Was maf from a good known source? using stock intake? Recirculating and/or blocked off the hole for recirculation on stock intake?

[bcrume]

it needs an air filter to run right, do you have an air filter? Check all the intercooler pipes for loose or broken clamps; there could be a small leak.

[silverarrow27]

It does not need an air filter to run right! When I first got my car running I didn't run an air filter for a good month. Even now sometimes when I clean my engine bay and take off the air filter I drive it without a filter for a couple days at a time.

[sikS1LVIA]

on top of that have u actually tested the maf not hooked up? if u take the maf off but still have it hooked up and blow through it you can check simple response from that... and dont forget to reset your ecu after u get the code to make sure ur not just getting an old code. i had a similiar problem and it was directly related to the tps sensor so make sure that shit is workin 100% or your maf will fuck up and the ecu may not give a tps code even if there is a malfunction.

[lightningph]

The wires on the wires to the MAF sensor plug matched up. I checked continuity to make sure they went to the plug they should.
I am running a filter.
I have a totaly new hose setup w/ intercooler and recirculating BOV. I have not checked for a hose leak yet but I would think it would have to be huge to cause it to run this rich at idle. I have checked the old MAF sensor by blowing across it and it seemed to be working right.
How do you reset the ECU? I had a error on the TPS sensor but after I replaced it the code stopped showing up.

[the head]

download the FSM for how to on resetting ECU and other informaiton

this is probably a vac leak spray all of your hose connecitons with soapy water rev and then look for bubbles

what kind of o2 gauge are you using

except for the stutter when you give it gas any other issues?

[lightningph]

Originally Posted by the head

download the FSM for how to on resetting ECU and other informaiton

this is probably a vac leak spray all of your hose connecitons with soapy water rev and then look for bubbles

what kind of o2 gauge are you using

except for the stutter when you give it gas any other issues?

I'm using a cheap one from AutoZone. I know widebands are far better, but this should be good enough for what I want to do.
The only running problem is not being able to hold a rev.

Originally Posted by sikS1LVIA

im telling u by your original description is has to do with either your tps, maf or both. they work together. i had the same exzact problem. sameeeee exact. first my tps went out .. actually it would randomley be gettting power then randomley not be getting power... and my intake caused my shit to lag soo bad... everytime i pressed the gas the fuking rpms dipped before they went up. make sure you dont have any leaks with your intake (turbo inlet) any leaks at ALL imean at all it will bog like shit and to reset your ECU codes=
1st. there is a diagnostic mode and a run mode.. each of these modes should be the knob turned all the right to the right or left... the left is run mode or dignostic and vise versa for the right side im not sure which is which. but anywayz if your ecu is set up right it should be all the way to one of the sides alredy and theres an arrow. it should be pointing the oposite way of the way you have it fully turned already (assuming its set up right once again) so heres wat you do
2. turn it the way of the arrow which should be oposite of the way u have it turned... if its the other way around do it anywayz. turn it until it stops. leave it there and turn on your car, then shutting it off about 2 seconds later
3. after u have shut the car off turn it back to the way it was before the operation
4. check your codes

I haven't driven it since replacing the TPS b/c it was still running badly, but before it would accelerate until about 5psi and then act like it was hitting a rev limiter. I think this was b/c the TPS droped resistance after a certain point. If I don't reset the ECU will it still run in safe mode even if the problem is fixed? I will check for leaks and let you know what I find. THanks

[the head]

do not look at your o2 gauge it's useless and serves no purpose unless it is a wideband or you are at full throttle

the 3500 rev limiter is the limp home mode and yes you need to clear it before it will go away on certan trouble codes

[lightningph]

Originally Posted by the head

do not look at your o2 gauge it's useless and serves no purpose unless it is a wideband or you are at full throttle

the 3500 rev limiter is the limp home mode and yes you need to clear it before it will go away on certan trouble codes

I can rev all the way to redline as long as I am not getting on it to the point where it gets 5psi of boost.

[sikS1LVIA]

im telling u by your original description is has to do with either your tps, maf or both. they work together. i had the same exzact problem. sameeeee exact. first my tps went out .. actually it would randomley be gettting power then randomley not be getting power... and my intake caused my shit to lag soo bad... everytime i pressed the gas the fuking rpms dipped before they went up. make sure you dont have any leaks with your intake (turbo inlet) any leaks at ALL imean at all it will bog like shit and to reset your ECU codes=
1st. there is a diagnostic mode and a run mode.. each of these modes should be the knob turned all the right to the right or left... the left is run mode or dignostic and vise versa for the right side im not sure which is which. but anywayz if your ecu is set up right it should be all the way to one of the sides alredy and theres an arrow. it should be pointing the oposite way of the way you have it fully turned already (assuming its set up right once again) so heres wat you do
2. turn it the way of the arrow which should be oposite of the way u have it turned... if its the other way around do it anywayz. turn it until it stops. leave it there and turn on your car, then shutting it off about 2 seconds later
3. after u have shut the car off turn it back to the way it was before the operation
4. check your codes

[sikS1LVIA]

and ive also heard that recirculating your BOV casues some problems on some setups. ive got an open bov and it runs great. oh but also about the laggyness and it wanted to die... wen im drving it happens atleast once a trip where the car actually dies from the rpms dipping so low..... and i know for a fact its all from my maf = intake. ive got a ghetto ass intake on it right now and its leaking. so im choking my turbo of air

[the head]

Originally Posted by sikS1LVIA

and ive also heard that recirculating your BOV casues some problems on some setups. ive got an open bov and it runs great. oh but also about the laggyness and it wanted to die... wen im drving it happens atleast once a trip where the car actually dies from the rpms dipping so low..... and i know for a fact its all from my maf = intake. ive got a ghetto ass intake on it right now and its leaking. so im choking my turbo of air

no that is because your BOV is atmosphered and you are venting metered air

[sikS1LVIA]

what do you mean it didnt reset? if your getting the same codes then your getting the same codes. unplugging the battery for 24 hours will not do anything the ecu is a brain it basically saves your messages. and u said there was a leak after the maf right? knew it. what codes are you getting now? still tps?

[silverarrow27]

Disconnecting the battery to reset the ecu only works for some Toyotas from my knowledge.