Jump to content


Help,car stops then starts


i claudius

Recommended Posts

Help ,sometimes i will be driving along(manual gearbox) and the engine will stop as if there is no petrol ,a second later it bump starts and all is well for another week or so the engine light comes on and then eventually after a few stops and starts just goes off ,the main dealer and other garages find nothing wrong ,any ideas? thumbsup.gif

Link to comment
Share on other sites

It sounds suspiciously like an intermittent fault. whistling.gif

Seriously - the dealer should be able to plug in to the ECU and diagnose the fault. It could be anything from contaminated fuel, a poor electrical connection, faulty ignition system, faulty fuel pump, air in the fuel lines, blocked fuel filter, faulty sensor/s.....literally anything.

When the engine stops, does your dashboard die as well? That would indicate computer/electrical. Or does a warning light (ECU ) come on when the motor dies? Or is the issue temperature related?

Try and determine a few more things to help diagnose. Maybe next time it happens, depress the clutch to stop it from bump starting, come to a halt and then try to key start it and see what happens with the dash/warning lights etc.

Back in the old days you'd just check all the electrical connections, clean out the carby, and that solved 90% of the problems like this. If it didn't then you'd swap out the coil and Bob was probably your Aunty.

These days the only thing recognisable to me under the hood is the battery.blink.png

Edited by Gsxrnz
  • Like 1
Link to comment
Share on other sites

Thinking outside the box, there's a very slight chance the fuel cap is clogged creating a vacuum in the fuel tank. When the engine stops, undo the cap and see if there's a sound of air being sucked into the fuel tank.

Link to comment
Share on other sites

How much fuel is left in your tank, or is it full?

Are you going uphill at the time, faulty fuel pump?

Or is it just the crap/grunge left in the bottom of your tank.

As mentioned by another poster, get your car on the Highway and thrash it for 30 minutes, dont drive with the warning light on.

Link to comment
Share on other sites

If you can find the ECU, unplug it then reconnect..

If you do this, make sure that your body is grounded before touching the ECU or the wiring harness attached to it.

Disconnect the battery cables.

Static electricity can jump from your body while touching the ECU, and it will cause major damage.

You can guess how I know this ... SnapOn makes a neat little wire with an alligator clip on one end and a velcro band on the other to attach to your wrist.

Link to comment
Share on other sites

for a fiver, you can get a blue tooth connector for your ECU and it'll read it out on to your phone/tablet/laptop. Not that it will solve the problem, but it's nice to have a glimpse at what the garage is looking at.

Edited by wilcopops
Link to comment
Share on other sites

Thinking outside the box, there's a very slight chance the fuel cap is clogged creating a vacuum in the fuel tank. When the engine stops, undo the cap and see if there's a sound of air being sucked into the fuel tank.

Beat me to it Farma-

-had exactly that problem with a V8 Rover--took a while to discover--then it was by chance, one time I thought I had run out of fuel-although it showed quarter full ---could be the fuel gauge ? - I opened the cap to pour some fuel in and heard that sucking sound- left the cap off- and away it went--stopped and got a new cap--no more problems---

Link to comment
Share on other sites

Thanks for all the advice boys , as to driving it with the engine light on ,its been on and off for nearly a year and my friend drove his pick up with the engine light on for 18 months ,never found the problem. only worry if it flashes on and off. light on

Link to comment
Share on other sites

Thinking outside the box, there's a very slight chance the fuel cap is clogged creating a vacuum in the fuel tank. When the engine stops, undo the cap and see if there's a sound of air being sucked into the fuel tank.

Beat me to it Farma-

-had exactly that problem with a V8 Rover--took a while to discover--then it was by chance, one time I thought I had run out of fuel-although it showed quarter full ---could be the fuel gauge ? - I opened the cap to pour some fuel in and heard that sucking sound- left the cap off- and away it went--stopped and got a new cap--no more problems---

Tends to be a problem with older cars - the breather hole on the cap blocks........ it's so nice when you find the solution to a mystifying problem and it costs nothing or just a few cents!

Link to comment
Share on other sites

Thanks for all the advice boys , as to driving it with the engine light on ,its been on and off for nearly a year and my friend drove his pick up with the engine light on for 18 months ,never found the problem. only worry if it flashes on and off. light on

What do you mean by "engine light"???

Link to comment
Share on other sites

Thanks for all the advice boys , as to driving it with the engine light on ,its been on and off for nearly a year and my friend drove his pick up with the engine light on for 18 months ,never found the problem. only worry if it flashes on and off. light on

What do you mean by "engine light"???

the engine management light.

Link to comment
Share on other sites

I had a similar problem with a 2.8 Ford Granada, would drive no problem then would cut out, you could leave the car stood for an hour or add more petrol to the tank, then it would start and run no problem.

The cause of all this mayhem was a balloon in the tank, being sucked into the fuel line as the pump drew fuel from the tank.

The reason the guy sold me the car, as they could not find the problem.

Regards Tom

  • Like 1
Link to comment
Share on other sites

Thinking outside the box, there's a very slight chance the fuel cap is clogged creating a vacuum in the fuel tank. When the engine stops, undo the cap and see if there's a sound of air being sucked into the fuel tank.

Beat me to it Farma-

-had exactly that problem with a V8 Rover--took a while to discover--then it was by chance, one time I thought I had run out of fuel-although it showed quarter full ---could be the fuel gauge ? - I opened the cap to pour some fuel in and heard that sucking sound- left the cap off- and away it went--stopped and got a new cap--no more problems---

Tends to be a problem with older cars - the breather hole on the cap blocks........ it's so nice when you find the solution to a mystifying problem and it costs nothing or just a few cents!

Not supposed to have a breather hole on modern cars with evap these days, not supposed to vent to atmosphere, supposed to be recycled back through the engine with the Evap system, closed loop, only supposed to vent through a charcoal canister. Does the engine light code say anything about the evap system? There is supposed to be a constant vacuum on the system of about -1.5 to -2 lbs to prevent atmospheric venting, if there is not a vacuum the engine light will come on and it will indicate a system leak so the vacuum system needs to be checked, had a hole in the vent line of my VW back at the fill line under where it recycles into the charcoal canister, before I discovered it I bought a new gas cap, no difference, once I found and fixed it, light off no more problems.

There is a Schrader valve under hood some where on the Evap lines, be careful you don't confuse it with an A/C valve they look very similar but the Evap should have a label on it. If you take off the cap (it should have) push on it, it should let out a slight sucking sound, if it does not there is a vacuum leak, if you do push it no worries it will come back up with the engine running in short order on it's own, but the problem exists still and needs to be located and repaired, if that's what is required by the ECU code.

Edited by WarpSpeed
Link to comment
Share on other sites

Thinking outside the box, there's a very slight chance the fuel cap is clogged creating a vacuum in the fuel tank. When the engine stops, undo the cap and see if there's a sound of air being sucked into the fuel tank.

Beat me to it Farma-

-had exactly that problem with a V8 Rover--took a while to discover--then it was by chance, one time I thought I had run out of fuel-although it showed quarter full ---could be the fuel gauge ? - I opened the cap to pour some fuel in and heard that sucking sound- left the cap off- and away it went--stopped and got a new cap--no more problems---

Tends to be a problem with older cars - the breather hole on the cap blocks........ it's so nice when you find the solution to a mystifying problem and it costs nothing or just a few cents!

Not supposed to have a breather hole on modern cars with evap these days, not supposed to vent to atmosphere, supposed to be recycled back through the engine with the Evap system, closed loop, only supposed to vent through a charcoal canister. Does the engine light code say anything about the evap system? There is supposed to be a constant vacuum on the system of about -1.5 to -2 lbs to prevent atmospheric venting, if there is not a vacuum the engine light will come on and it will indicate a system leak so the vacuum system needs to be checked, had a hole in the vent line of my VW back at the fill line under where it recycles into the charcoal canister, before I discovered it I bought a new gas cap, no difference, once I found and fixed it, light off no more problems.

There is a Schrader valve under hood some where on the Evap lines, be careful you don't confuse it with an A/C valve they look very similar but the Evap should have a label on it. If you take off the cap (it should have) push on it, it should let out a slight sucking sound, if it does not there is a vacuum leak, if you do push it no worries it will come back up with the engine running in short order on it's own, but the problem exists still and needs to be located and repaired, if that's what is required by the ECU code.

here come the "engineers" - be prepared for a massively complex explanation with equally expensive solutions........or....run out and get a massively cheap pinch of salt.

Link to comment
Share on other sites

Sorry if my understanding and explanations offended you somehow? Actually no I'm not. This is a forum for knowledge and assistance is it not? Or is it that I just explained away your post about breathing holes in fuel caps that ruined your day? I don't understand why people wish to both remain ignorant and to create conflict or make snide remarks against valuable info. when they post outdated nonsense? You and a couple others brought it into the thread I merely made sure it was properly disseminated, now what was your problem again?

FYI It didn't cost me a thing to locate and repair my own problem with my car, I just replaced the perforated piece of hose with a new piece I had already.. It's BECAUSE I had the knowledge that it costed me nothing, not the other way around...

Link to comment
Share on other sites

  • 1 month later...

At last problem solved ,i took it to the big yellow building on Sukhumvit a week ago the one by the banglamung police station that sells second hand parts ,guy there checked it said you need spark plugs ,but i am prettysure its the "map sensor" changed the plugs ,no change so took it back two days later and he fitted a new "map sensor" 1500 baht took a few minutes ,yippee problem solved.thumbsup.gif now why after three days couldnt chevrolet have solved the problem ? yet he did after 5 minutes?

Link to comment
Share on other sites

Sorry if my understanding and explanations offended you somehow? Actually no I'm not. This is a forum for knowledge and assistance is it not? Or is it that I just explained away your post about breathing holes in fuel caps that ruined your day? I don't understand why people wish to both remain ignorant and to create conflict or make snide remarks against valuable info. when they post outdated nonsense? You and a couple others brought it into the thread I merely made sure it was properly disseminated, now what was your problem again?

FYI It didn't cost me a thing to locate and repair my own problem with my car, I just replaced the perforated piece of hose with a new piece I had already.. It's BECAUSE I had the knowledge that it costed me nothing, not the other way around...

Warpy, Thank you for sharing your knowledge with us.wai.gif

Link to comment
Share on other sites

  • 2 weeks later...

Could also be a MAP sensor - manifold absolute pressure

Indeed it could seedy. I was thinking about what may have been lost in the Thai pronunciation of English. smile.png

Pretty much the same thing anyway. Here's a very simple and clear video explanation of how it works:

http://www.youtube.com/watch?v=gq4szm5Re0g

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.