motor stall out at hight rpm

[LE759]

Mark I changed out the AFM with another I had and it cured the fuel pump from running all the time. The miss is still there but tomorrow I am going to change out the cold start valve to see if that cures my cold weather problems. I'm thinking that because I had crud in the fuel filter that I might have some in the inlet of the fuel pump. The car acts like it is starving for gas after 2000 rpm's in 3rd, 4th and 5th gear. Does this make any since? I will eventially need to use the spare AFM on my other car; what can I do to fix it?

[So Cal Mark]

ohhhh, you kept that little tidbit of information from us; if the filter was full of debris you probably have injectors that are partially plugged. More than likely you'll have to remove them to get them cleaned.
As for the AFM, if the only trouble with it is the pump switch you can adjust that if you remove the black cover.

[LE759]

Mark there wasn't a lot of debris in the filter, just a little. The filter looked new and the fuel injectors are new. You don't think that there could be a problem with the inlet of the fuel pump?

[Jimb]

if you're going to compare Fiats and women it all comes down to one thing, when it all goes badly with either one you can still spend the night with the Fiat

...both are more fun topless...

[dartme]

Hope you don't mind me jumping in here le759. Mark this is Dave I talked to you about my '79 carbed stalling at high rpm's( around 2000 to 3000 rpm's) when i picked up my '70. but it only happens when the the engine is hot .I put a new filter in( it was dirty) and checked the sending unit it looked good and it's still stalling. I checked the filter again and its clean.Once the engine stops it will start right up again. what can I look at next?
Thanks Dave

[So Cal Mark]

I would check fuel pressure and the integrity of the hoses on the inlet side of the pump; both at the tank and the fuel pump. Also check the inlet screen in the carb inlet

[SpiderJim]

Anyone mention removing and seeing if the pump itself is dirty? Mine was and it was new. Tapping it out got all kinds of black bits. Hence a thorough hot dip cleaning of the tank (really bad) new pump and filter with injectors out and cleaned. I also tried a hi-flow pre-filter to the pump just for insurance after the tank filth I found. Also found the PO had not used Fi rated tubing so replaced that. Fuel now flows like Niagra

[majicwrench]

If I have this issue in a car that comes into my shop, I will hook up a pressure gauge and verify what is going on with the fuel pressure, it eliminates all this guessing. Gauge gets "Teed" into line, then strung up to windshield and usually secured on a wiper arm, then off I go. Pressure should not drop on acceleration. If it does, something wrong with pump, filters etc. If fuel pressure stays up, then start looking at air flow meters, restricted injectors etc.

On cars with mechanical pumps, at the same time I "T" in a vacuum gauge BEFORE the pump, I can really see what is happening then.
Keith

[So Cal Mark]

good tips

[dartme]

Thanks guys, I will look at the lines and fuel pump. But why does it only happen when the engine is warm? When we drive it at night sometimes it wont start to stall for 30 minutes into the drive.

[boogiedude]

Thanks guys, I will look at the lines and fuel pump. But why does it only happen when the engine is warm? When we drive it at night sometimes it wont start to stall for 30 minutes into the drive.

Maybe you have a choke problem. Could be that your choke is set wrong and isn't opening fully once the engine is warmed up. Hence the stalling once warm

[LE759]

I'm sorry I'm new at this, what should the fuel pressure be?

[dartme]

OK, I check the lines and they looked ok. i noticed that the new fuel filter was less then 15% full of fuel when the engine is running. shouldn't it full? thanks

[So Cal Mark]

no, the filter won't be full on a carbed car

[dartme]

Ok, So if there is fuel is getting to the filter and the filter is clean and getting to the carb do you think that is where the problem is? In the carb? Thanks