Hello, first post as a member here. I've been looking around in the forums with no luck about my issue. I recently bought a 2003 cobra, the car had a small bog at idle when the AC is turned on. I figured it was the IAC. I've replaced it twice with no luck, one was a duralast brand and the other was a Delphi brand. I've smoke tested the car for vacuum leaks and found nothing. I also had the car tuned by VMP and it still has not resolved the issue. I have done all maintenance to the car with no luck. she has a 2.76 pulley, 2# lower, borla ataks with longtubes and an Accufab single blade TB. Please any suggestions would help immensely.
2003 Cobra keeps bogging when AC is on HELP
- Thread starter joel0314
- Start date
Check the voltage at your TPS, it should be somewhere between .95v and .98v. You can make adjustments by loosening the screws and changing it's position. Unmetered air can also cause this condition through loose vacuum fittings and open breathers.
When you turn on the AC it should actually boost your idle a tad.
It drops from about 800 to 600 -650 and then once you go into coastng while driving it will bog down to about 400 rpms and sometimes even shut off
When VMP tuned it did you tell them about the A/C issue?
Yes, even sent them a datalog of me turning on the AC and revving and rhe car bogging. They can't pinpoint it remotely.
That's odd. It should show up in the idle duty cycle.
It might be worth doing the whole idle set up and see if it helps. Since you're running an Accufab I wonder if the IAC doesn't have enough room to make up for the load of the A/C?
It might be worth doing the whole idle set up and see if it helps. Since you're running an Accufab I wonder if the IAC doesn't have enough room to make up for the load of the A/C?
What do you mean by whole idle setup? Sorry pretty new to these
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What I do is get the car warmed up and set up a datalog to watch the IAC duty cycle. With the engine idling I open the throttle blade until the IAC duty cycle shows 30%. When you open the blade the RPM will go up, but the IAC will take it over and bring it back to whatever is commanded. Once it hits 30% I lock the adjustment screw. Then check the TPS and set it to .97-.99vdc. It should be good after that.
Will be trying that out Wednesday when I get out of work. Thank you
Do you have the stock alternator in the car?
Whats the voltage reading? When ac is running?
So I was able to get the TPS Absolute reading at 198 from 235 prior. Adjusted the idle and smoke checked for vacuum leaks. No lvacuum leaks found, no change in idle issue. Car idles fine when warm and AC off. When it's cold it bigd and dies and has to be given gas to stay on. Also same issue as before with the ac on wether cold or at full temp, still bogs down to 400 rpm and comes back up
TPS Absolute is a different reading than IAC Duty Cycle. You need to check IAC Duty Cycle when adjusting the throttle stop.
Sure your AC compressor is in good shape and AC system doesn't have restrictions?....
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