Thought I resolved this but my 97 is acting up again.

Had an intermittent 'engine fault' on start, or should say no start.
Engine cranks fine but no start and fuel pressure is good.

This would happen after longer drives of over an hour, and a couple of times when I made many short errands throughout the day. Car runs fine, shut off at destination then go to start and it gives and 'engine fault'.

Wait about 20 minutes and car starts and runs fine. Couldn't get any codes on my innova reader until one day when I got a engine fault/poor vehicle performance on my way to work (first time while driving and engine ran rough). Was able to pull the P code and description of cylinder 1 miss fire, bank 1.

Been a few years since I did plugs so I changed those out and no more issues for about a month. Engine fault came back with same senario but never while driving.

Still no codes to read but had been about 5 yrs since battery so I put a new one in and it seem to have resolved the issue.

Issue just popped up again and the only thing I can think of is the Ignition Coil Relay is well really old and maybe overheating. It either starts or doesn't, but runs great when it does.

Anyone have any ideas of how to track this down or any similar experiences?

Thanks for any advice.
Dan

 

One of the indications of ECM failure is a occasional misfire. If it gets worse you might consider sending it to a service like Automotive Scientific for testing. The 97 ECM's appear to particularly subject to failure.

If the problem persists on #one, try swapping the ignition modules and see if the fault transfers. If not, it's likely the ECM or coil/plug.

 

autoecu.com did my ECm on my 97 when I owned it. That damn car had all sorts of issues showing via warning lights. I was like, that is just too much to be those indvl parts and knowing that the 97 EMC's had issues I sent it out, they bench test and fix it needed. Mine never had another issue.

 

Thanks for the info guys but I don't think it's the ECM. Keep that for future reference though.

Only once did I have the misfire, and after changing the plugs, no issues with that. Plugs were done about 6 months ago.

The only thing that happens is either starts and runs fine, no messages, codes or anything, just like another day.

Or it doesn't start which only happens after long drives, and try to restart shortly after, within 5-10 minutes of turning off. When that happens, just have to wait a little while (20 minutes or so), then starts right up with no messages or codes and runs perfectly fine.

'Engine Fault' is the only message I ever get when it doesn't start. No codes detected with the scanner.

When no start, engine cranks fine but doesn't try to fire and displays 'Engine Fault'. Like I said, I'm stumped.

The only thing I can think of it is used to being driven daily and this showed up because the car had been sitting for a few weeks. Probably the culprit even though the battery is only 2 months old.

 

Mine is the 97 so it has the two ignition modules and also a ignition coil relay.

I was leaning towards the relay because of the no start condition with no fire even though it's cranking and has fuel pressure.

Wasn't sure of what the start-up cycle (process) is on the car and when the ECM will cut-off fuel. I'm sure it's not the inertia switch because I don't have to reset anything when it starts, just wait a little bit.

 

I didn't understand previously. That sounds like a vapor lock. There was at least one thread dealing with it recently, try doing a search.

 

Thanks RJ, I didn't consider that and I'll check it out.

 

Doesn't sound like vapor lock but read a similar situation a member posted in a vapor lock thread where three relays in the LH fuse box under the hood had worked loose and caused what seems to be similar to my symptoms.

Even though mine only happens after car has been driven a while so not sure if they worked loose but maybe on of the three is the ignition coil relay I mentioned earlier.

So I'll have my Father check those to see if any are loose.

By the way he has the 97 now.
Gave it to him after I got the 07, but I still fix it for him.

I'll let you guys know how it works out and sorry about the confusing first post. I tried to state the issue as clearly as possible but apparently I have problems expressing my thoughts

 

Hi.
You may want to check these four relays, both for proper seating, contact and internal conductivity. Use a small amount of electronic cleaner. Do not use WD40.

 

Thanks Oyster, I thought they were on the driver's side so cool.

I'll forward it to my Father, he's retired now so I'm sure he has time to check them.

Any idea on what values they should read with the continuity test?

 

Talked to my father and he did a visual inspection of the relays and all looked fine, nothing loose but he didn't know how to check them. Said they looked brand new, no corrosion or even wear marks on terminals.

Had him pick up a couple relays anyways. Dealer had them for $6.00 each so told him to replace them and I'll get the old ones and check them later. Figured for $12.00 just replace the ignition coil relay and the fuel injector relay.

Probably one or the other and car is in storage for the winter, so I guess we'll find out next year if that was the issue. Try and update this post then but with no codes coming up I figure its got to be one or the other.

Keep fingers crossed.