1998 Cobra - Crank but no start

[Daniel_Mc]

I am at a loss here guys. This all started about 5-6 months ago and with holidays and life I have only had a few available weekends to look into this. The car in question is a 1998 Cobra with 62.5K on it. The car has an intercooled P1SC, still retains the IMRC’s, catless X and 3:55 rear gear. The only other engine modifications I can tell the car has are monoblade TB and MSD coils. I do not know about the injector size or fuel pump specs; I purchased the car several years ago as it sits. I took the car out one afternoon and all seemed fine. The following day I went to move the car out far a wash and it would not fire, only crank over. The fuel pump is priming and the car has pressure at the rail. I did some other trouble shooting and research; after checking a few things found the car had no spark. I changed the two coil packs with the correct Motorcraft units with no change. After that I had someone tell me it could possibly be the PATS system. After some research I replaced the key and the ring in the column with no change still. I found that by bypassing the inertia switch in the trunk the car will run very poorly for a couple of seconds. After checking multiple grounds and wiring I gave up and took the car to a local shop and am being told the ECM is bad. What are everyone’s thoughts on what is happening here? Also what other options do I have for PCM/ECMs other than OEM? I do not want to repin or rewire anything; would prefer plug and play. My next issue is that if I do replace the ECM with a new unit the car will need to be retuned, I cannot locate anyone that can dyno tune this car. Two things I neglected to mention – The last few times the car was driven I was getting DTC P0172 System too rich bank 1. The code was sporadic and would not always appear. The next thing is the alternator failed and I had the unit rebuilt and reinstalled it. I am unsure if this is worth mentioning however in the back of my mind I can’t help but think if the unit was not rebuilt properly this could have caused the ECM failure?



Any input is greatly appreciated - Thanks!

 

[xblitzkriegx]

the things that happened before it didnt start are interesting. its entirely possible ecm was failing and cause the other things to occur. letting it sit could have cause something inside the ecm to fail.

 

[ashleyroachclip]

Do you have a check engine light when you turn the key on ?
If yes , does it go out when cranking the engine

 

[98 svt]

Is the theft light flashing, what is the pattern? (2 blinks...pause...followed by 3 blinks for example)

 

[Daniel_Mc]

Do you have a check engine light when you turn the key on ?
If yes , does it go out when cranking the engine

ashleyroachclip,

Yes, I do however when cranking over the "service light" will go out and only the theft light is blinking. I have a few videos however having an issue posting them here.

Is the theft light flashing, what is the pattern? (2 blinks...pause...followed by 3 blinks for example)

98 svt,

Yes, theft light is flashing does not appear to be in any specific pattern. I will verify and as stated before when i figure this video posting thing out I'll get those up. Likely my firewall here at the office.

-Daniel

 

[Daniel_Mc]

 

[98 svt]

Turn the key to just On and see if the the theft light is doing anything fishy.

 

[ashleyroachclip]

It does appear the check engine lamp is doing what it is supposed to do .
Theft light on , appears to go out as the engine tried to run ?

 

[Daniel_Mc]

Turn the key to just On and see if the the theft light is doing anything fishy.

I will get an updated video as soon as possible. The car is not stored close to me. I do have this one video I shot however the inertia switch has been bypassed so the car ran for a few seconds. You can not touch the gas or it will instantly kill on you.

 

[ashleyroachclip]

Theft light I believe is supposed to flash when car is off , not sure .
The fact that it goes out when the engine starts, is correct .
Can you pull codes ?

 

[Daniel_Mc]

Theft light I believe is supposed to flash when car is off , not sure .
The fact that it goes out when the engine starts, is correct .
Can you pull codes ?

Yes, able to pull codes and nothing is pending at this time.

 

[Daniel_Mc]

Is the fuel pressure where it needs to be? I am just double checking everything again before I got down the ECM/PCM route.

Thanks,
-Daniel

 

[Daniel_Mc]

Revisiting this thread - The ECM was not the issue, after lots of trouble shooting we located a Diablo MAF IA (PN F7373) in the PS fender zip tied to the bottom of the frame. We bypassed the box and the car fired right up. Can't get into boost but at least the issue is resolved.