I recently sent my ASM 58mm back to them for a part that was wearing out. While it was there, they replaced everything and honed it out even bigger and put some new butterflies in it.

Well, I get it back and put it on. It wanted to idle at 1,300RPMS no matter what. My IAC counts were 130 and the TPS voltage was .68volts.

The first thing I did was call ASM. They didnt offer much help, but mentioned I might have a bad IAC motor. I told them it wasnt bad when I sent it to them. (I sent the TB with all the sensors still attached).

These are the things I tried yesterday.
1. I bumped the idle screw to open the blades enough to lower the IAC counts to 30.

2. This pushed the TPS voltage to 1.00volt and TPP (scanmaster) was at 1%.

3. I pulled the TPS off and slotted the holes to bring the TPS voltage to .56volts. (this lowered the RPM to 1,050-1,100)

I cannot get it to idle any lower than that!!! IAC counts are good, and TPS voltage is good, what else can I do?

I have a feeling that this may have to be taken care of in my PCM program because now the TB is bigger than 58mm.


Thanks,
Jeff Stewart

 

The computer should use the IAC to try to lower the idle speed to the programmed RPM. Your IAC counts should lower as the computer trys to bring the idle down. Over 100 is too high for idle. Is the IAC counts moving? They may have damaged the IAC motor putting it back in if it doesn't move. If the IAC does get down to zero and the idle speed is too high then you would need to crack open the throttle blades some.

 

Yes, the IAC is moving back and forth freely. Going down the highway I see around 70. As I am coming to a stop it will go down t almost zero and then work its way back up to 30.

I may try to advance the throttle blades a little more like you said.


Jeff

 

Did you use a new TB gasket?

 

Anyone else have any ideas or insight?

Jeff

 

Yeah sure did. Buttttt, the gasket they send is PAPER THIN!!! You may be on to something there

 

Everytime I changed throttle bodies-they would idle high-it took the pcm a few days to learn everything and then the idle would be normal.

 

yup

 

Sounds almost like a bad TB gasket or intake man gasket allowing extra air to rush in. Are you seeing split BLMs? From my experiences, the computer will "re-learn" VERY quickly

 

The BLM's are split at idle. But while going down the road they are very close.


I finally got the idle down last night!!!!!


But I could only accomplish it with the IAC counts at 60.
That put the RPM at 975-1025
TPS voltage at .54
TPP still at 00
IAC stabilizing at 60-64


If I brought the IAC counts to 30, the idle went right back up to 1,300-1,400RPM and sometimes it even brought the TPP up to 03-04


So I guess I'll have to live with it for now.


Thanks for all your help guys If you have any more insight please let me know and I'll try it tonight.


Jeff