Intermittent engine cutting out - ideas?
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 801
Likes: 6
From: United Kingdom
Intermittent engine cutting out - ideas?
I have a stock 1976 euro car that has suddenly decided to intermittently cut out. This appears to be electrical because when the engine dies the rev counter drops to zero - when the engine comes back on line (after only a few seconds) there is a backfire as it clears the fuel. Can drive for miles without a problem and then - bang! - then will run again without a problem. When it first happened it kept happening every ten minutes or so but since then only occasionally. Last time I was flooring the throttle and the engine was under max load.
Doen't think its the spark box - been told they either work or not. Could it be the coil?
Any suggestions?
PJC
Doen't think its the spark box - been told they either work or not. Could it be the coil?
Any suggestions?
PJC
Advanced
Joined: Aug 2003
Posts: 58
Likes: 0
Sounds like something I just spent the summer searching for. In my case, the the RPM did not drop to zero unless I kept my foot on the gas. If I backed off the throttle just a little, I could save it and keep it running. Each time I got in the car, it didn't happen until I was a least 10 miles down the road, and then only intermittently.
We all elictiral sensors were testing within their specified values. We replaced the throttle position sensor, a couple of spark plug leads, the distributor cap and rotor, the DME relay etc.
A very SMART Rennlist participant suggested I have the wrench replace the temperature head sensor. (Don't know if it applies to your vintage). Just before replacing, the wrench tested it one more time and finally got it to fail. When replaced, it ran like new.
Don
We all elictiral sensors were testing within their specified values. We replaced the throttle position sensor, a couple of spark plug leads, the distributor cap and rotor, the DME relay etc.
A very SMART Rennlist participant suggested I have the wrench replace the temperature head sensor. (Don't know if it applies to your vintage). Just before replacing, the wrench tested it one more time and finally got it to fail. When replaced, it ran like new.
Don
RL Technical Advisor
Joined: May 2001
Posts: 11,870
Likes: 75
From: Portland Oregon
PJC:
Your car, being a CIS-equipped auto, doesn't have some of the items that Don has,...
I'd be looking at:
1) All of the electrical connectors to the fuel pump & fuel pump relay as well as the relay itself
2) CD box and connectors
3) Coil
4) Battery cables; front & rear.
Your car, being a CIS-equipped auto, doesn't have some of the items that Don has,...
I'd be looking at:
1) All of the electrical connectors to the fuel pump & fuel pump relay as well as the relay itself
2) CD box and connectors
3) Coil
4) Battery cables; front & rear.
Advanced
Joined: Sep 2003
Posts: 68
Likes: 0
From: Redmond, WA
If it's acting like someone is reaching across and turning the key off and then back on ("tach goes to zero and then back fires when it comes back") I'd be suspect of the 12V power (or a ground) relating to the ignition system from the battery thru the fuse and key switch to the box ....... maybe 
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