foxbody chip tune questions

[svtnotch]

Im coming down in may with new york mustangs crew. I have 1987 Mustang 347 with prom 80, 30 lb injectors and mass air conversion using a 1989 stang a9l and harness. What is the chip tune is it external add on chip or do you reflash my a9l. Car drives and idles great but has a stalling problem. If i have idle set at 750-900 rpm it will idle great but stall while pushing in clutch coming to a stop. I turned idle up to 1000-1100 and it fixed the problem. Id like to turn idle down without the stalling. Will your chip tune fix this issue? Thanks

 

[vorstang]

did you adjust your tps switch?

 

[svtnotch]

Yes i adjusted the tps voltage to .99 volts.

 

[1BIGMOFO]

My 94 was stalling bad before I had it tuned at MM last summer.

 

[svtnotch]

Rob was it stalling at idle or when you were pushing clutch in coming to a stop? Did they reflash your computer or add a chip did mm tune fix it? This is 1st time getting tune just wanna make sure im set for trip. Dont wanna get down there and find out its $450 + chip.

 

[A.J.]

The chip (external) will address your stalling problem, if it is a tuning issue.

 

[vorstang]

it could also be the way that you adjust your idle

 

[svtnotch]

I always set base idle by following instructions from a ford tsb. At idle unhook iac /adjust idle to lowest /turn engine off reconnect iac/ disconnect battery 5min/start and fine tune. Thats from memory may not be exact i have tsb printed in garage. Always worked good for me in the past.

 

[vorstang]

what i do is give the car a big vacuum leak and then unplug the iac,shut car off, reconnect vacuum, start car, adjust idle, then plug in iac.
by giving the car the big vacuum leak the iac closes, so then when you adjust idle there is no controlled vacuum leak by the iac

 

[svtnotch]

Fords TSB 91-7-4

 

[vorstang]

i know, but i do it the way i described and it never fails me. just thought i would throw it out there for ya

 

[svtnotch]

Thanks ill give it a try when i get it back together. Now i need to find out about the chip or no chip.

 

[cobra20sc]

remember that the combination you have is far different stock in terms of airflow, different throttle body, intake, displacement, etc. (at idle or anywhere else). You have to tell the computer what the airflow is at idle so it can manage it better. There is one scalar and one function that needs to be adjusted and a procedure to determine the values. A chip tune (or any other way to adjust these settings like the tweecer) will fix it. I have an article from the Tweecer boards if you're interested in reading more on it.

-chris

 

[svtnotch]

Chris send me the link to article id like to check it out.

 

[cobra20sc]

Here are 2 pdf's that I used to tune out the idle issues I had which were the same symptoms than what you have. One is a tweecer forum post which describes the procedure on how to tune it. The other is an article someone put together installing a bigger throttle body and then tuning it. The tuning stuff starts on page 3 of 4. Let me know if you have any questions on it.

-Chris

 

[cobra20sc]

ok apparently the file size on pdf's is very limited . . duh!?!?:smash:

PM me your email address and I can email it to you.

-Chris