Please listen to this 30 second clip - cold start issues
10-13-2011, 07:11 PM
#1
Burning Brakes
Thread Starter
Please listen to this 30 second clip - cold start issues
On cold start up (sitting over night) then engine bogs down for the first minute if the throttle is blipped or try to take off slowly. In the audio clip, you can hear it from 18 - 29 seconds.
It's at the dealer and under CPO, but the tech was not sure from the sound clip, plus he doesn't have a long window to hear it. Once the secondary air pump shuts down, the throttle is normal. Nothing abnormal after that first minute. It's been happening for about 1 week.
Any ideas? I told the tech I would do some research to see what I can find. Maybe it will help him look in the right direction since he only has about 1 minute to listen. Of course he will see if there are any codes, but no CEL at this point.
10-13-2011, 07:19 PM
#3
Race Director
On cold start up (sitting over night) then engine bogs down for the first minute if the throttle is blipped or try to take off slowly. In the audio clip, you can hear it from 18 - 29 seconds.
It's at the dealer and under CPO, but the tech was not sure from the sound clip, plus he doesn't have a long window to hear it. Once the secondary air pump shuts down, the throttle is normal. Nothing abnormal after that first minute. It's been happening for about 1 week.
Any ideas? I told the tech I would do some research to see what I can find. Maybe it will help him look in the right direction since he only has about 1 minute to listen. Of course he will see if there are any codes, but no CEL at this point.
If the gas is ok then my WAG is the engine's lean at cold start. I'd look at the engine coolant temp and intake air temp readings before start -- but with the key on -- and then monitor these readings during the engine's cold idle time.
Sincerely,
Macster.
10-13-2011, 08:04 PM
#5
Burning Brakes
Thread Starter
Trending Topics
10-13-2011, 08:49 PM
#8
Burning Brakes
Thread Starter
10-14-2011, 11:37 AM
#11
Burning Brakes
Thread Starter
He thinks it could be carbon build up on the intake valves. As a hail mary, he's going to replace the MAF since it's still under CPO...gotta love these guys helping me with parts like this.
It will be documented and if it gets worse, hopefully PCNA will provide help after CPO coverage ends next month. Not sure if carbon build up is covered by any warranty whether new or CPO, but it didn't sound like it.
10-14-2011, 01:06 PM
#12
Welcome to my world....
If you don't give it any gas...just let it sit there...does it bog? Do the rpms drop and it sounds like its choking?
If so, you have EXACTLY what I have. The dealer has had my car 3 times looking for this issue.
As your tech to check for misfires with his computer when he does a cold start.
So far...my tech has:
Changed all the plugs
Replaced 2 injectors with new ones
Checked/flushed the fuel rails
Checked the MAF
Cleaned the throttle body
Checked the coils (4 are new from last year)
Checked for vacuum leak
So far, nothing he's done has corrected the problem. Personally, I'm starting to think there might be a glitch with the DME.
Let me know what you find out!!
sean
If you don't give it any gas...just let it sit there...does it bog? Do the rpms drop and it sounds like its choking?
If so, you have EXACTLY what I have. The dealer has had my car 3 times looking for this issue.
As your tech to check for misfires with his computer when he does a cold start.
So far...my tech has:
Changed all the plugs
Replaced 2 injectors with new ones
Checked/flushed the fuel rails
Checked the MAF
Cleaned the throttle body
Checked the coils (4 are new from last year)
Checked for vacuum leak
So far, nothing he's done has corrected the problem. Personally, I'm starting to think there might be a glitch with the DME.
Let me know what you find out!!
sean
10-14-2011, 01:46 PM
#13
Burning Brakes
Thread Starter
Picking it up today and will take it back next week when they get the MAF. Probably won't fix it, but I'll take a free MAF.
I'll ask if he checked misfires.
