Engine starts. Dies when warm., !st time running in a few years. Options

[Crash207]

Hi guys.

Started engine 1st time in years. Fired right up. ran for a few mins and died, sat for a few mins and started up again. Fuel pump runs constantly, added 2nd inline fuel filter just to be safe. fuel lines are new, everything else is old. any ideas where to start?

Thanks in advance.

M@

[SirAndy]

any ideas where to start?

Maybe with more info? (IMG:style_emoticons/default/biggrin.gif)

Size? FI? Carbs?


If it's a D-Jet, check the CHT and make sure it's connected and firmly screwed into the head.

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[Jeffs9146]

If it's a D-Jet, check the CHT and make sure it's connected and firmly screwed into the head.

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[Crash207]

Stock D-Jet. Stock ignition, book says ignition trigger is a possible cause, will pointless ignition replace/fix this?

[Jeffs9146]

If it starts fine when cold and after a few minutes starts to stumble then dies it is the CHTS or the Aux Air Regulator!!

[injunmort]

could also be indicate bad coil. see if it is leaking or cracked in cap.

[Tom]

Similar problem here.
http://www.914world.com/bbs2/index.php?showtopic=129035

[Prospectfarms]

Similar problem here.
http://www.914world.com/bbs2/index.php?showtopic=129035

Heck, my fuel pump stopped working again last night, so I'm not finished:

My 1.7 d-jet dies at idle speed after 15 minutes. But after repairing vac leaks I was able to keep car running by feathering throttle.

After running for 5 minutes I can clamp the Aux Air Switch hose with a minie vice grip and drop idle to 900. My AA is bad, but it's not killing the engine.

Check electrical resistance to CHT and MPS when engine cold and then right after it stalls.

Resistance values courtesy of Anders.

MPS primary coil
Pin #7 and #15 (At the ECU 25 pin connection.)
90 ohms
(check each lead and make sure there is no continuity to the MPS case)
#8 and #10
MPS secondary coil
350 ohms


Check resistance of CHT at pin 23 and ground (pin 11) Should show 2K ohms at 68 deg. F and drop to below 100 ohms at 200 F. CHT resistance should drop as it gets hotter. If not, your engine can flood.

Check coil wire for fat blue spark after engine dies. If not, check positive primary coil lead (wire at +coil terminal for power. If power to coil and coil not spark -- bad coil or fried or misadjusted points. (I don't care what anyone says, but a bad capacitor (condenser) will not prevent either the coil or the plugs from sparking.)

pwr to coil, good coil, and good points, but no no spark at any plugs = bad distributor, and despite what you might hear or read, it is not uncommon to see an electrical failure inside a distributor, esp. if it is not OEM. This can manifest after warm up.

Do you smell gas after car stalls out. Smell the exhaust when you think the time is about to come. Exhaust that is acrid or irritating to your sinus, not painful, but unpleasant, after you stick your face close to the tailpipe, is a telltale of a rich mizture. If so, Then the AAR or CHT are suspect.

If it dies lean, your fuel pump might be cutting out when it gets warm.

Believe it or not I was experiencing both problems at the same time. Talk about confusing. It might be fixed, but since my FP is temp. out of service, I'm not sure. If it still dies, I'll perform a second check on MPS, but I just got a vacuum pump, so as soon as I can get some fuel pressure, I'll be able to rule out the MPS.

Sounds a bit confusing? Its not. My order of work was to check FP pressure, sort through the ignition, set the timing points,and dwell (point gap. Check whether the AAR was working and if not whether the engine would run without it (it did). Test electrical resistance of CHT and MPS when cold and when hot. Double check the fuel pressure after the engine is warm, then check whether the MPS holds a vacuum. If you do all that and solve any problems the tests reveal, and you still can't keep it running, throw all your tools at the car.

Don't forget to check if plugs fouled after engine dies.

Keep trying it might take some time!

[swl]

Fuel pump running continuously is a sign that someone has 'fixed' a relay board problem by tying into another power source (frequently the ignition). You should have a look to see what they've done.

Not likely this is a fuel pump issue - is it still running after the car dies?

'ignition trigger' is it possible you are reading about the 'trigger points'. Located at the bottom of the distributor - rear side. Trigger points tell the ECU when to fire the fuel injectors. I've never heard of them failing hot and running cold. Other than some creative prototypes there is no substitute for the trigger points.

The fella's above have the most likely solution. The AAR is designed to add air (and thus RPM) when the engine is cold. A heater coil activates a thermostat (bimetalic - like a toaster) that shuts off this air flow as the car warms up. You should hear your revs dropping through that process.

The CHT is the equivalent of a choke. Rich when cold, lean when hot. It does this by adjusting the length of the fuel injector base pulse.

Can you describe (or record) what it sounds like as the engine dies.

"fuel lines new - everything else old". If you are running original vacuum lines replace them. So many D-Jet problems can be traced back to leaking vacuum lines. Not likely this is your current problem - but it will be a problem sooner or later.