Jump to content

Recommended Posts

After another 70 kilometer trouble free drive, I parked car to tend to other business. When I started car an hour later and drove about 100 meters it slowed down with no accelerator response, sounded and acted as if it was starving for fuel backfired loudly two or three times,recovered and I drove another 20 kilometers without problem. An hour later it started perfectly but stalled after about fifty meters a dozen times, always acting as if it was starving for fuel but with loud backfire now and then. The only thing I did during the day was top up fuel tank. From an amateur, could vapour lock have caused this? Any other ideas please. I have an electric fuel pump. Nothing else I can think of that may be significant.Thanks, Paul

Link to post
Share on other sites

It might be dirt in the fuel blocking the pump's filter. If so, the inside of your tank might be shedding small particles of rust, which get carried down the fuel line.

Have a look at Section K3 of the Technicalities CD, but be aware that the latest fuel, with higher percentage of methanol, is said to attack some sloshing compounds.

Ian Cornish

Link to post
Share on other sites

Sounds more electrical than fuel to me Paul. The backfiring could be because you have unburnt fuel mixture being pumped into the exhaust, which ignites when the engine fires up again. I had a similar thing some time ago which turned out to be an intermittent connection on the LT side of the ignition.

 

Rob

Link to post
Share on other sites

If its emptying the float chambers of fuel and then stalling you'll hear the fuel pump clicking fast when it restarts. If the fuel pump does not do this then its not running out of fuel, and suspect ignition.

Link to post
Share on other sites

It's too early to disturb the neighbors testing the above responses but I should mention also that I have the 1-2-3 ignition system which so far has performed perfectly. But a loose wire connection is always possible.

 

When I topped up tank, three of the four pumps at the petrol station were marked "defective"...I tank there most times, never had a problem. Now I'm wondering if the fuel might have been contaminated. And, the owner, who is very seldom there was running the place himself...If one of the ladies is there this morning I'll try to find out if they had a fuel problem. It's an independent station, no brand, I use it because it's next door to my garage and they sell fresh donuts. Thanks again for tips. Paul

Link to post
Share on other sites

Paul,

"Defective?"

If the misfiring start after the fill-up then I would definitely suspect water in the fuel.

It will settle at the bottom of your tank and be pumped along with fuel to the float chambers, where it will settle again and be sucked preferentially to the jets.

Cure is to drain the tank of the water, which if you are lucky will come out first, and you wont need to remove the whole tankful of petrol. The fuel that's left will have lost ethanol but should be OK until you find healthier source of petrol (and sustenance! )

Peter

Link to post
Share on other sites

Sounds more electrical than fuel to me Paul. The backfiring could be because you have unburnt fuel mixture being pumped into the exhaust, which ignites when the engine fires up again. I had a similar thing some time ago which turned out to be an intermittent connection on the LT side of the ignition.

 

Rob

I with Rob,

Definately could be a spark issue. EG: Deteriorating hot coils, condensers on their way out, weak sparks under compression can do strange things (and don't get me started on the deluge of fake chinese Bosch, NGK and Champion spark plugs flooding in via eBay). I spent ages trying to resolve what I thought was a fuel starvation issue with another of my cars. I fitted a new redtop Facet pump and pipework, Malpassi regulator, cartridge filter, moved the pump to the boot (thinking heatsoak) and then in desperation took it to Steve and Steve at Track 'n Road (top guys, I trust nobody else for race-tuning old cars, even if they are a pair of grumpy old men...). Straight away one of the Steve's said "coil" I was not convinced as it was a fairl recent and expensive item so he pulled the coil from his dyno rig and fitted it to the car. It is still on there now and never had a problem since...

Link to post
Share on other sites

It's too early to disturb the neighbors testing the above responses but I should mention also that I have the 1-2-3 ignition system which so far has performed perfectly. But a loose wire connection is always possible.

 

When I topped up tank, three of the four pumps at the petrol station were marked "defective"...I tank there most times, never had a problem. Now I'm wondering if the fuel might have been contaminated. And, the owner, who is very seldom there was running the place himself...If one of the ladies is there this morning I'll try to find out if they had a fuel problem. It's an independent station, no brand, I use it because it's next door to my garage and they sell fresh donuts. Thanks again for tips. Paul

All pumps will access the same underground storage tank so I would imagine the pumps themselves are defective, not the fuel

Link to post
Share on other sites

Hi Pâul

I had a similar problem with my 1-2-3 ignition when in France for CLM meeting. It turned out to be the LT lead to the coil which was loose fitting, so I pinched it up with the pliers and ran it into a small town garage and he fitted shrink wrap on the wire and that did it.

 

Dave

Link to post
Share on other sites

had a pro from around the corner stop in. He tested electrics for a half hour and declared my 1-2-3 distributor was defective. I ordered it Thursday, received it noon Friday, installed it and it still didn't work...I tested coil myself and can't get a spark out of it. This is an expensive hobby...will try to new coil in the morning.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.