XFlow randomly stops running, why and how to fix?

[TexasDreamer]

1991 XFlow twice over the last 4 months has stopped running for no apparent reason. The first time I was decelerating on a frontage road about to turn off and it just quit. No hiccup, no sputter. Needles on the gauges went to zero and the engine stopped running. I coasted to a stop in a safe place, thought about it for a minute, then turned the key and it started right up. Yesterday I was making a left turn through an intersection at low speed and it just quit again. I didn’t notice the gauges. I started it up while still coasting and it ran fine all the way home. At twice in four months it’s very intermittent so it will be hard to know if I’ve really fixed it. Any idea on what’s wrong and how to fix it?

[CarlB]

You have a loose connection or broken wire that is disconnecting intermittently would be my guess and where I would look first. If everything goes dead start at the battery and check all the connections. Pay special attention to the ignition switch. If you are only loosing power to the engine, check all the wiring in the ignition system. 

[sf4018]

Does sound electrical, hopefully something simple and obvious like a loose ground wire.

[coffee break]

I'll give another vote for dodgy electrical connections. With the engine running, try wiggling wires related to the ignition (except ones with high voltage from coil and to the plugs) and see if it quits. 

[Kitcat]

I had a similar  problem on my ‘97 X-flow powered Caterham. It was so intermittent it was impossible to find. But it only happened on start up, never while under way.
 

So we started replacing everything we could think of. Never solved it. Then the starter went bad. In looking at it my mechanic found a loose ground wire: intermittent starting problem solved.

[bball7754]

Do you have a Pertronix ignition in the distributor?  I had an intermittent issue with the Crossflow in my Mallock which got worse and worse.  It finally cut out on track at Road America, and it wouldn’t start.  I had a spare ignition, which I installed, and it still wouldn’t start.  It had fuel, and electric from the coil to the distributor.  I had read that the normal brown color rotors can be a problem.  Pulled the rotor, and showed it to an extremely knowledgeable mechanic who prepares vintage race cars.  He took a one second look at it and said it was bad, and was shorting out.  I found a replacement red rotor at the track, put it in, and it started immediately.  No issues since.

 

Steve

[SENC]

Slightly poor ground at chassis on cable from battery is what did the same to my Elan - took just the right circumstances to cause the issue so seemed similarly intermittent. 

[TexasDreamer]

Wiggling the key didn't cause the failure. Pawing all around under the dash didn't' cause it either. All the lights, horn etc. work as expected so no matter how messy the wiring is, it's functional and I'm not inclined to spend time figuring out what was done and why. So far, I have cleaned up a lot of electrical connections. Before I worked on them, I wiggled and pulled to see if engine stopped. No luck so it's hard to know if this will fix it or not. Cleaned up the Alternator connections, the ground connections as directed in the Owners Manual, the fuses, the ignition switch. I'm going to let it ride and see what happens. Thanks for all the advice.

[coffee break]

Intermittent electrical problems can be frustrating, maybe you could burn incense and chant "Lord Lucas".

 

(I couldn't resist)

[Anker]

Here are a couple more suggestions, based on my own experience with my X-Flow:

 

Check the connections to the alternator. The spade connectors can be loose and in my case the indicators and horn would only work at idle. It had been that way for years for the previous owner. I discovered that one of the spade connectors was loose. I tightened it and presto, problem gone permanently.

 

Check the connections at the fuse box and how well the fuses are held.

 

Good luck!

 

Anker