Wont boost over 5llbs??

[eyesoarer6]

Hey all, Im still having issues with my 1.5 build. The car is driveable now but it sputters pretty bad when I get on the gas, this only happens when the car gets warm/operating temp. When I gently accelerate the thing drives smooth but it wont boost over 5lbs. But when I boost up to 5lbs the car PINGS and sounds like it doesnt have anymore to give.

Another issue I have is when I first fire up my car in the morning, it idles lower than normal. About 1500-1200 RPM cold start, but when it gets warm it drops down to 400-500 rpm like its about to stall.

I had my ECU recapped recently from DM and it didnt help. Only thing I did was new NGK plugs gapped at .028, autometer oil pressure gauge and boost gauge. Other than that the build is all stock.

What would cause my car not to boost over 5lbs? And, any suggestions on my other problems would help.

The car is a 92 Lexus SC300 with a 1.5JZ.

 

[destrux]

Is the fuel pressure ok?

 

[eyesoarer6]

I dont have a fuel pressure gauge hooked up so I really cant say. Whats the fuel pressure spec for these 1JZs?

 

[hvyman]

Codes?
Boost leak?
tps?
isc?

 

[eyesoarer6]

Codes?
Boost leak?
tps?
isc?

No more codes, I had a KS code prior but had it repaired.
No boost leaks
How would I test the TPS?
Sorry but What is ISC? No too familiar with the acrynoms yet?

 

[hvyman]

Di 187. Need a multi meter.
http://www.97supraturbo.com/1997 Service Manual/Diagnostics-Engine.pdf

Isc is idle speed control valve. Check the tps first.

 

[Gritz]

If you are having cold/hot start issues check the temp sensor.

 

[eyesoarer6]

Would a 2JZGTE Map cause this? Are they compatible with the 1JZ? I bought a 2JZ MAP from a forum member and Im not sure if its good cause he sold me a bad ECU.

How would I test the MAP sensor, voltage vacuum?

 

[hvyman]

resistance.

2jz map sensors work fine with 1jz's. Are you sure the ecu is bad?

 

[eyesoarer6]

resistance.

2jz map sensors work fine with 1jz's. Are you sure the ecu is bad?

ECU is fine, had it recapped by Aaron at DM. I had bought a bad ECU(no start) but picked up another one. My buddy had a brand new TPS, I swapped them out and the problem still persist.

Im thinking low fuel pressure or bad MAP sensor. How would I check resistance on the MAP sensor?

 

[destrux]

Fuel pressure should be about 43psi with the vac disconnected.

 

[eyesoarer6]

K, I was messin with the car after work today and found out that my car is running LEAN. I dont have the CEL ON but decided to see if the computer was storing any codes, so I pulled a code 25 Mixture control contiuesly LEAN.

Would a GE fuel damner cause low fuel pressure? How would I perform a fuel pressure test on a 1JZ? Where would I tap in to?