Rex Ruby

I have been having some drivability issues and am looking for feedback as I am getting ready to start digging into this. Some background:
A few years ago I was having similar drivability issues and it ended being the ECM. In the course of trouble shooting this I had installed a new MSD opti along with some other new parts. I’ve read the negative about the MSD but didn’t think it had been a problem for me.
Current issue is the engine cuts off. Sometime it comes back other time I have to pull over and eventually it will restart. Let me back up a little here, right before this started I noticed that the engine was requiring a longer start time. Before this that engine would start with the key in the start position no longer than 4 seconds. Quick start every time since I’ve owned this (18 years). Figuring the original injectors are 24 years old with 141K I decided to purchase new injectors from FIC. The new injectors didn’t solve the start problem. I called FIC to discuss and they had sent the wrong injectors. FIC sent the correct ones. Upon initial installation and testing, very noticeable improved pedal response BUT still not any improvement on the starting time. So it didn’t hurt to upgrade the injectors but that didn’t solve the start problem or the cutting out problem. Driving home from work a few weeks ago it cut out and I was lucky to be able to pull over into a parking lot. As I stopped the car I noticed some smoke from under the hood, jumped out, opened the hood and fire! Was able to extinguish easily and no damage. I think when it cut out and I was working the gas pedal in an effort to try to keep it running I loaded the exhaust with gas. Flat bedded home (first time in 18 years!) and sitting in the garage waiting for diagnosis and repair.
First thing I am doing is pulling codes if it will let me. OF course if that points to the opti then I’d replace it. Is the feedback going to say the MSD opti is crap? The OEM opti the MSD replaced I believe it still good and had about 20K on it. Would you reuse it? The ECM I replaced (a few years ago) would throw a CEL when running on the highway for about an hour. No codes and would reset upon restart. Could that be an indication that is marginal?
Looking for any feedback/suggestions!

A Peter C4

You say original opti may be good, was it replaced by someone with the MSD just to change. I mean was car running correctly when swap was done? Just reread your post, I would open old opti, check for clean and reseal it,replace MSD with original or get another new opti, not MSD. No fire damage?

Cliff Harris

The first thing I would check is for a ruptured fuel pressure diaphragm. Pull the vacuum line off and turn the key to on (without starting). There should not be any fuel in the vacuum line.

That is the prime symptom of a problem in the EGR system. The ECM does the test when the engine has been running at steady state for over 4.5 minutes. The only time that happens is out on the highway.

Rex Ruby

I changed the opti a few years ago to the MSD when I was having drivability issues. I'm headed in the direction of replacing it. Doesn't appear to be any fire damage, putting it on my lift this weekend

Rex Ruby

No fuel in the vacuum line, I'll look at the EGR system, thanks

Rex Ruby

Tonight I check the vacuum line and I have fuel in it. Guess I'm replacing the press. regulator

Rex Ruby

UPDATE: Thanks to Cliff, I did find the fuel pressure regulator was passing fuel into the vacuum side. Replaced it and the start issue is solved it is now starting like it always had in about 3 seconds. Drivability seems to be solved as well. Also replaced the clutch line that was the only item slightly damaged by the fire. All seems good, now I can back to some of the projects I've had on the list for the Ruby!

cv67

Good that Cliff found the fix for you! Sometimes a lazy 02 can do that also

Havent seen you post forever

Rex Ruby

Funny how that happens!