Bad running issues

Engine Oily Bits, Ignition, Fuelling, Cooling, Exhaust, etc.
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wrighty
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Bad running issues

#1 Post by wrighty »

Right keep getting running issues ,Some days it's ok some times it's terrible

This weekend I have had bad issues thou

The car is misfiring , also the car keeps cutting out at speeds , so having to bump start it as I drive down roads , keeping the gas pedal down it's fine , it has troubles when driving at normal speeds , I have checked the diaphragm I have checked plugs and the dizzy ,rotor arm , they seem ok , there's no cracks in the dizzy cap

It idles terribbly and also the fuel pipe to the Carbs runs over the top of the engine and sits imbertween the thermostat and rocker cover , so could it be the fuel vaporising , also a wire going from the coil to the dizzy cap doesn't look too smart

I'm a bit lost , has anyone got any ideas
Dan Wright

1973 2.5pi
1986 E28 bmw 5 series
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valencia
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Re: Bad running issues

#2 Post by valencia »

As you have checked the carbs I am thinking you need to go back to the ignition system. A faulty condenser can cause some of these problems, usually worse when hot. A few years ago I had quite a few running problems on my 2000. I was checking all sorts to no avail. I gave in and went to a proper tune up place, ie full computer diagnostics, rolling road etc.
When the car was connected up to the computer it showed six graphs for the individual sparks. All were ok with high peaks until it was revved up, then all the peaks dropped down. Engine was ok at tickover but the ignition system could not cope with the increased load for high revs. The principle cause of this was was very high resistance in the carbon brush in the distributor. It was showing as much resistance on it's own that you would normally expect in the whole system.
I'm not sure what resistance figure you should normally get but it solved the problem having it replaced. Good luck.
tony
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Re: Bad running issues

#3 Post by tony »

Have you a spare coil you could substitute to see if this is the problem? I'd also replace the wire if it's at all suspect. All 2000's had the fuel pipe in the same position so I doubt if this would be causing problems.
1976 2500 TC. converted to S specs.

Lots of bits

1999 BMW Z3.
2006 BMW 325ti.
Hopefully not needing too many bits.




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dallliiisss
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Re: Bad running issues

#4 Post by dallliiisss »

wrighty wrote:Right keep getting running issues ,Some days it's ok some times it's terrible

This weekend I have had bad issues thou

The car is misfiring , also the car keeps cutting out at speeds , so having to bump start it as I drive down roads , keeping the gas pedal down it's fine , it has troubles when driving at normal speeds , I have checked the diaphragm I have checked plugs and the dizzy ,rotor arm , they seem ok , there's no cracks in the dizzy cap

It idles terribbly and also the fuel pipe to the Carbs runs over the top of the engine and sits imbertween the thermostat and rocker cover , so could it be the fuel vaporising , also a wire going from the coil to the dizzy cap doesn't look too smart

I'm a bit lost , has anyone got any ideas
Hi,
I had a similar problem with my Pi a while back, and it was two things wrong, a faulty coil, and a fuel leak. If you have a spare known-good coil I would try it and see if that improves things. If not, it sounds like your ignition system could do with a service:Leads, Plugs, Points etc, and go from there. Your fuel system could also be in need of a once over. Try changing the fuel filter(if ones fitted)making sure you have no resrictions, and a good flow of fuel.

Also if you have Zenith carbs fitted, you may want to check the diaphragms for perishing.

Regards,
Lee Smart
1971 2.5 PI saloon
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CAR
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Re: Bad running issues

#5 Post by CAR »

wrighty wrote: It idles terribbly and also the fuel pipe to the Carbs runs over the top of the engine and sits imbertween the thermostat and rocker cover , so could it be the fuel vaporising , also a wire going from the coil to the dizzy cap doesn't look too smart

I'm a bit lost , has anyone got any ideas
The fuel pipe does not pass that high usually. As I remember the estate one and every other carb big saloon has the pipe passing under the thermostat housing. A picture of David Withers very nice 2500 here viewtopic.php?f=33&t=1639&p=11889&hilit=battery#p11889 does show the fuel pipe feed to the carbs. As can be seen and if I understand your description correctly, the pipe is not between the housing and rocker cover.

What type of fuel pump do you have? Our estate had an after market one without external primer. It's output was always questionable and if you ever ran out of petrol it would not pull the petrol up once you added some. An NOS one soon fixed this.
Added to the pump having to raise the fuel higher than usual to get to the carbs, because of the fuel pipe positioning, it could be many small things adding to a bigger outcome.

Good to meet you at the Notts meeting the other day Dan

Cheers Colin.
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Mike Stevens
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Re: Bad running issues

#6 Post by Mike Stevens »

To add to Colin's post, the petrol pipe should be held in a little right angle clip (with a rubber sleeve inside it) hanging off the lower water pump housing to head fixing bolt. The right angle clip puts the pipe partially underneath the casting in the water pump housing.

The cutting out sound more like ignition that fuel though to me. I have known the wire from coil to distributor be faulty such that the engine cut out on LH bends as the engine moved!

Make sure that the wire inside the distributor is OK and not shorting to earth. Remember that the plate moves with manifold depression.

Cheers,
Mike.
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wrighty
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Re: Bad running issues

#7 Post by wrighty »

Thanks all

It does seem to cut out when warm , that would explain condenser I surpose . I have ordered points condenser and a coil so I hope it helps
Dan Wright

1973 2.5pi
1986 E28 bmw 5 series
marino
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Re: Bad running issues

#8 Post by marino »

hi have had similar problems rescently and i found my exhaust valves had recessed (after changing just about everything)resetting the valve clearances have improved it no end at least now it idles like it should previously it was ok ish cold but terrible hot, am still havin problems which i will post now for some enlightenment .I was using an additive (wurth) but it failed to protect

Marino
lives in shrewsbury shropshire
works at mbp autoservices shrewsbury

1977 2.5 s family airloom
1975 fiat 124 coupe
1983 fiat strada abarth wreck.
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