engine seems to running rich

[n29we]

Hi everyone - I've posted a couple of times about bringing my D back to life after its 15+ year sleep. I had it running really good until about and hour ago. I shut it off to run into a store, came out fired it up and it now runs like it getting too much fuel. It has been running great till just now. It's got a new fuel pump unit, accumulator and fuel filter as well as a working cold start solenoid. I popped the air cleaner off to check operation under there and all appears normal in the operation. What should I look for next? Any and all advise would be appreciated Thanks Jim O

[NightFlyer]

Are you sure it's running rich and not lean?

Is it just under idle, or constantly?

[Rich]

Similar question about your question - what makes you think it's running too much fuel?

If you are smelling unburned fuel then you either have a fuel leak or your catalyst isn't performing.

Feel free to post more symptoms so we can help.

[David T]

Similar question about your question - what makes you think it's running too much fuel?

If you are smelling unburned fuel then you either have a fuel leak or your catalyst isn't performing.

Feel free to post more symptoms so we can help.

Do your eyes burn from the exhaust? Is the catalytic convertor or the muffler turning red?

[n29we]

Ok it probably is running lean. What would be the culprit or culprits? It has a new fuel pump, accumulator and fuel filter. Has been running great till the other day. Haven't jumped into the injector system yet. Comment / suggestions?

[NightFlyer]

We still need more info to provide any kind of directed help, otherwise, it's the shotgun approach.

Do you have a manual or an auto? Is it running poorly only under idle, or all the time? Does the running change at all cold vs hot?

Perhaps if you could post a video of the engine running, it could help.

The first thing to always check for when poor running is occurring is for any vacuum leaks. Make sure all the vacuum hoses (that you can access) are properly seated where they're supposed to go by following the diagram on the vacuum routing label that's on the underside of the engine cover. Then, you can either use the carb cleaner method or the smoke machine method to check for any non designated line leaks that might be present. With the carb cleaner method, you're spraying directed blasts of carb cleaner around the engine while it's running and noting any surges in rpm associated with the spraying. If you notice any such surges, then you have a vacuum leak in the vicinity of where ever you made the directed blast of carb cleaner, and must locate and remedy the situation causing it. The smoke machine method is using smoke so that you can visually see and identify a vacuum leak.

Without knowing more about the problem that's the best I can offer without having you check virtually everything, as anything from fuel to ignition to compression could be causing a poor running condition.

Best luck!

[hmcelraft]

Since it happened after a shut down according to your input - it would seem that something did not come on when it was re-fired. I'm thinking the lambda/frequency valve. If that is not "on" it would run like it is starving for gas.

Easy stuff - check connection on frequency valve. Check the RPM relay or replace it with a new/known working one. Check the lambda relay functioning.

[Rich]

Initial post: I had it running really good until about and hour ago. I shut it off to run into a store, came out fired it up and it now runs like it getting too much fuel......Subsequent post: Ok it probably is running lean.

We can provide better answers if we understand the symptoms. Running lean and running rich are results. How about a few symptoms or differences you notice between "really good" before and whatever it is doing now?

Can you describe how your engine is running? Or why you think it is probably rich/lean?
- Rough idle?
- Stumbles on acceleration?
- Misfiring on a regular basis?
- Hard to start?

And under what conditions?

[kings1527]

You mentioned you did a lot of work to the fuel system, such as replace the pump, accumulator, and filter.

Any time the system is opened up to that degree, chances are you'll need to adjust your dwell with a meter. Did you do that after replacing those components?

[n29we]

Since it happened after a shut down according to your input - it would seem that something did not come on when it was re-fired. I'm thinking the lambda/frequency valve. If that is not "on" it would run like it is starving for gas.

Easy stuff - check connection on frequency valve. Check the RPM relay or replace it with a new/known working one. Check the lambda relay functioning.

I agree! It almost seems like there are electrical issues with the cars long sleep. The car started yesterday and ran fine. I've had turn signals work then not work, same with the windows. Now the alternator is off line, was indicating 13+ volts now it's showing 12. I guess I'll have to start checking grounds??

[Flash66]

Do a full tune and replace old vac lines.


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