Engine dies after VPC hard wire

[V8hntr]

I recently installed an HKS vpc w/550 chips into my car but since my harness (87-88) didnt fit into my 89 supra I decided to hardwire it and used the 2.4k ohm resistor into the AFM plug and followed the newer connection chart on this thread:
http://www.supramania.com/forums/sho...t=vpc+hardwire

I removed my lexus AFM and replaced it with a pipe and installed my IAT sensor onto the ic pipe next to the 3000 pipe and installed the Map sensor onto the manifold vacuum lines. When I start the car it has a rough idle, and black smoke comes out the back and my plx systems wide band registers 14.7. After about 30 seconds the A/F richens and withing about 20 seconds it becomes richer than 11:1 and the engine dies. Last time I took it out for a drive it did not boost more than 4 psi and the engine just kept stalling. I adjusted the idle, gain, ouput, knobs but it doesnt make any difference. I really dont wanna go back to the lexus/AFM setup . Has anyone had these symptoms?

thanks
Hamed

 

[dbsupra90]

remove the resistor and see if it makes a difference. it is only for air intake temp and will just set a code is all.

do you have another map sensor you can borrow to rule that out?

are you running an afc?

 

[empera]

check ur codes.

 

[V8hntr]

remove the resistor and see if it makes a difference. it is only for air intake temp and will just set a code is all.

do you have another map sensor you can borrow to rule that out?

are you running an afc?

no I am not running and afc. I did remove the resistor it doesnt make a difference. No unfortunately I dont have another map sensor.

 

[V8hntr]

check ur codes.

OK I will.

 

[empera]

if u get code 31 then that means for some reason its not getting a AFM signal. Also check ur map sensor, unplug it and see if it does the same.

 

[V8hntr]

if u get code 31 then that means for some reason its not getting a AFM signal. Also check ur map sensor, unplug it and see if it does the same.

ok I will check for this. thanks alot.

 

[V8hntr]

ok I will check for this. thanks alot.

Ok , I get a code 24 which is the intake air temperature sensor. I have already disconnected my AFM plug, the VPC IAT is new and I tried connecting and disconnecting the MAP sensor but doesnt make a difference to engine operation. It idles fine for a while then becomes rich and then stalls. I checked my VPC to ECU wiring too. There are only 4 wires AFM, Power, Ground and rpm. They are all hardwired and correct. I dont know what else to to.

 

[empera]

the iat sensor might be bad. Know anyone near by that has a working vpc that u can borrow the sensors from?

 

[V8hntr]

the iat sensor might be bad. Know anyone near by that has a working vpc that u can borrow the sensors from?

NO but I will see if I can purchase IAT sensor from other members.

 

[turbogate]

I'm not sure how much of a difference that makes, but did you double check the dip switches settings?

 

[V8hntr]

I'm not sure how much of a difference that makes, but did you double check the dip switches settings?

hi Greg:

No Actually I did not check those. I have to open the case dont I? It doesnt have any screws .

Hamed

 

[empera]

yea theres small tabs on the sides, just be careful and u should be able to snap the the top off.

 

[turbogate]

Here is how they should be set on the 89+ in case you did'nt have the diagram:

 

[dbsupra90]

you may also try to unplug and reseat the chip. be careful tho, they are static sensitive.

 

[thejrman]

thank u turbogate i have been looking for a wireing diagram now i can get my car running

but the only thing is that my wiring for my vpc dosent have a gray wire i have red white blue black brown and yellow