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View Full Version : 1998 Corvettte cold start issue (MAF DELETE related?)



Brad Kimbler
December 8th, 2014, 02:56 AM
I received a 1998 corvette with not 3-4 in a 60e, I pulled the trans and rebuilt it, no issue, the customer then wanted to fix his cold start issue

I Pulled the tune(no MAF on the car) and started to look at it...

During a LOG the commanded desired airflow is at 0.00!!! and only runs when i give it throttle until 99degreesF then rpms jump up as desired airflow is now reading 2-3 grams/sec. In the tune there is 3-4 grams/sec under 100F ECT, but I cannot understand why it isnt trying to add throttle by itself...Electronic Throttle should be the "IAC" correct?

I have noticed the speed density tune was somewhat incomplete, I set the p0101, p0102, p0103 to non emmisions, but it didnt help...do i need to get a custom OS in it???Is one even availiable for a 1998 car?

thanks for any help tips or tricks.

joecar
December 8th, 2014, 06:06 AM
Is the MAF physically missing...?

Do you have any logs of the cold start...?

Brad Kimbler
December 8th, 2014, 10:29 AM
Is the MAF physically missing...?

Do you have any logs of the cold start...?

Yes, Maf is gone and they cut the pigtail connector off, I can run another log and save it..

joecar
December 8th, 2014, 10:50 AM
Yes, Maf is gone and they cut the pigtail connector off, I can run another log and save it..Did they leave the IAT wires connected...?

Brad Kimbler
December 8th, 2014, 03:04 PM
Did they leave the IAT wires connected...?

Yes sir, I wasn't watching it to see the value, I'll double check to see if its reading but it was in the intake

Brad Kimbler
December 9th, 2014, 02:18 AM
I got a cold start log, added a few pids I think might be helpful, Notice the desired airflow is 0.00 until 99F ECT, thats where rpms jump up ...during the 99F and colder are I have my foot on the gas pedal, when it hits 99F it will idle without my foot on the pedal , I also noticed the OL to CL mode happens at 92F ECT , not sure if its related?

samuelkl
December 9th, 2014, 11:36 AM
Your B4307 looks like it needs to be lowered by 50%

limited cv8r
December 12th, 2014, 02:29 PM
Here is a File from Tune file depot, maybe do a compare and see if there is anything obvious to you, or try the stock tune in vehicle and see how it runs.