Engine "dies" At 1300rpm

[gotchopsticks]

Hey guys, my car is developing an issue that is very annoying. My car sat for about 6 months while I was deployed, but I think it was started a few times while I was gone. Once I replaced the battery it started right up, I filled her up with a fresh tank of gas(I stored it with Staybil) and changed the oil. Everything seemed fine for about a month, but just recently it has been acting weird. On a cold or warm start up, randomly in first gear about 1300 rpm, the engine seems to die for a 1/4 second or less and then jolt forward as if I just floored it. Electrical system stays on as far as I can tell, and it only does it in first gear. It is an '02 and has 81K on it, everything else seems to be fine. I did install the restrictor plate on the IAC, but that has been on for years and I never had this problem. I cleaned the MAF and the throttle body about a year ago, and only put on maybe 5k miles since then. This happens with the A/C on and off. Any ideas? Thanks!

 

[gotchopsticks]

bump?

 

[wmburns]

Suggestion. Start by getting an "add a Circuit" to add a pig tail to fuse F2.2 in the CJB. Use a VOM to monitor voltage on this circuit. Look to see if the voltage is dropping as this problem is happening. Repeat the test on circuit F2.8.

Also monitor RPM's with an ODB2 scanner while driving. Look to see if RPM's drop out when the problem happens. If the RPM's drop this indicates a possible problem with the CKP sensor.

FWIIW, this is most likely an electrical issue. If not power related, there's another sensor that is dropping out. MAF, fuel pressure, CKP, motor VPWR circuit. Recommend using the ODB2 scanner to monitor the MAF air flow for large changes when this problem occurs. Do the same for fuel pressure, and then TPS. Post the results.

99-04 fuse panel layout.
http://www.allfordmustangs.com/foru...r-swap-wont-fire-please-help.html#post2669271

 

[gotchopsticks]

Thanks for that, I'll try to get some readings but it happens so fast and so randomly that I wont have time to grab the reader and look at it before everything is back to normal. It never happens when the car is just sitting, only while driving, and it only happened twice last week. I can tell that the RPMs do drop, and then it feels as if I'm WOT immediately after. I do appologize, its been a while since I've browsed the forums and I am not familiar with some of the terms you are using, such as FWWIW, CJB, VOM, VPWR, and CKP.

Will the DiabloSport tuner on live reading settings be sufficient to get the info requested? Thanks.

 

[gotchopsticks]

Haven't figured out a way to get the readings while driving that were requested. However, there was another symptom today: I was driving as usual, car was warmed up, A/C going, and hit 1300RPM in 1st gear, it did it's hiccup thing, then the red THEFT light started flashing. At first it was very rapid, then a pattern emerged. It would flash 6 times, pause, flash once, pause, and repeat. This went on for roughly 3 minutes as I continued to drive then stopped. I shut the car off and started it again, no THEFT light and everything seems normal now. All help is appreciated, thanks!

 

[wmburns]

Check out the following post on how to get the cluster to display fault codes. Note, this may not work for your model year.

Note2, PATS will NOT disable a car that is already running.

I still think this is power related.

http://www.allfordmustangs.com/forums/v6-tech/49159-diagnostic-mode.html