Hi, I have a tpi setup with a 165 (maf system) on a conversion vehicle, The car has a surging idle and stalls sometimes. Also the cooling fan runs all the time. At the Ecm pin C1 is the cooling fan output. it is not grounded with key on but as soon as i start the engine the computer grounds this circuit. I have already tried 2 other ECMS with the same results.. any ideaS?

 

I would imagine its all with the same memcal ? Try grounding D11

 

3 ecms all with different memcals, im going to head out right now and ground d11

 

Depending on the programing the ecm will expect D11 to be n/o or n/c

 

Thanks, that worked when I grounded D11 the fan works at it should, now if i could get rid of this hunting idle and stalling I would be good to go!

 

Does it hunt just when you are slowing down ?

 

On a cold start it will idle at a decent rpm 800 or so, but once it warms up it starts jumping around then wants to die , the only way to keep it running is to turn the throttle stop screw up then it will stay running but at like 1000rpm or more, its a new IAC and the counts start at 80 and when it gets hot go to 0 when it won't idle

 

Have you set the minimum idle speed with the iac commanded in ?
Is this a automatic ? And are you making use of the park neutral adder ?

 

Regarding the radiator fan issue: Very important question here (Speaking from personal experience). Is your A/C still intact or was it deleted?

 

I have tryed setting min idle with IAC in all the way, not sure of the park neutral adder? and yes the AC is not there

 

OK, we're on the right track. Now I need you to check and tell me if the hard body line that goes from the accumulator to the condenser is still present. If not, look around the passenger side frame rail and tell me if you see a two wire connector. One wire should be blue the other gray IIRC.

If the body line is present, tell me if this connector is plugged into a switch on it.

 

In park or neutral when b10 is grounded the ecm will add to the target rpm to help aid with the engine load during transition into gear.

 

there is no connector left their or no sensor

 

What year is your car?

 

Hello, I am having a similar problem with the fan running all the time! I used to have ac but removed it. Any advice?? Thanks.

 

If your car is tpi and you have removed the ac ground pin D11 of the ecm or the blue wire from D11.

 

Thanks for the info! Grounding D11 worked. I appreciate the help!

 

if your car is pre-88 there is no need to drop the dash panel to get to the ecm. look at the passenger side frame rail. There should be a 2 wire connector that plugged into the switch on the aluminum AC body line that went from the condenser to the evaporator. Short these 2 wires and your fan should return to normal operation.

88+ didn't have this problem when the switch was unplugged because they changed the circuit to normally open.