95 Intermittent no-start without apparent rhyme or reason
Finally, this thing has given me an interesting challenge.
Since I got this car in December, it has had intermittent hard start issues. Most of the time, it fires right up after a second or two on the key. Other times, I can crank for 15 seconds and get nothing out of it, release the key and try again, and it fires right up. Once the car is running, there are very few to no run problems (slightly rich while cold, occasional misfire while coasting at low speed).
While irritating, I figured that whatever is causing that will eventually fail. It's getting close now. Monday, I tried to start the car to get to work and tried cranking for 10 minutes with no effect. (Well, I did uncover a slightly loose ground terminal which was corrected). Temperature was about 68 outside and the humidity was high. When I got home from work, I jumped right to diagnosing the car. I got my tools out and... the darned thing fired right up. Repeat the same for the next day. Wednesday and Thursday, the car ran great. :-/
I thought it might be humidity related...until Sunday. I drove the car before the NFL game to grab a pizza, and everything was great. Came home and it sat for about 5 hours, then refused to start. Temperature outside was about 91 and my mechanical gauge showed a cold engine. Came home several hours later, and the F-ing thing started up again.
So, I'm now at a loss. I have a sneaking suspicion that this is ignition related, as I can always smell raw fuel after enough attempts at starting. Unfortunately, every time I have a chance to diagnose, the damn thing starts and runs great. I would suspect PIP or TFI, but all the posts I've read on the subject seem to indicated that the no-start is when hot, leading to a consistent no-start condition. They also all seem to indicate rough running.
There is one other odd thing I noticed... When I am cranking (and the car is not starting), the check engine light blinks about once per second. With each blink, the tachometer jumps slightly. :?::?: I cannot find much information on whether that's normal behavior. Would be nice if someone could check (pull a spark wire and crank your car while observing the CEL to see if it does the same thing...)
Car Desc: Stock 95 5.0 with aftermarket H pipe, T5 manual. All emissions in place. No security. Base model with manual windows and locks.
Symptoms: Intermittent no start both hot and cold. (No attempts to fire) Will resume normal operation without any outside influence. Can smell raw fuel when it doesn't start, indicating that fuel is flowing. Once car does start, no drivability problems noticed. Fuel pump primes at Key On. CEL flashes once per second while cranking.
Suspected System: Ignition (PIP or TFI)
Parts replaced and known good:
-All grounds cleaned up and tested under load
-12.2v Engine Off, 14.2 Engine running with Subs, Headlights, Wipers, and Blower running at Max.
Engine Codes KOEO: 111 (system good)
Engine Codes KOER: 111 (system good)
Tried rapping against the TFI module sharply while engine running, no change.
Tried dousing everything under the hood with water while running, no change.
Tried light water mist to check for leaking spark plug wires (corona), no change.
Sorry this is so long. I'm just trying to get all the relevant information out there to save ya'll from having to ask the same volley of questions over and over.
"Oh Good, my Dog found the Chainsaw"
'95 Mustang GT, 5 speed, O/R H-Pipe
Current Needs to Polish this Turd: