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Bellamachinna · Posted: Wed May 11, 2005 3:25 pm Post subject: Vibrations And idle speed

Hi...

My 16v has developed a new gremlin... Sad

After changing the central muffler (the old one was rotten), the idle is gone... The car idles at about 1000/900 RPM, but sundenly dies. This happens especially at manouvres, when parking, when changing gear in traffic, when going out of an junction....
I also notice that the engine vibrates much more, and there is also a vibration on the steering columm (rummmmmmm), that deasapears if i hold the steering tight....
Is the central mufller creating to much back pressure???

All the best
J. Oliveira
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All'interno della mia macchina, vi sedete, tenete sopra e CHIUDETE IN SU...

alfafan · Posted: Wed May 11, 2005 4:46 pm Post subject:

You have a strange problem...
Its also dificult to say what is happening without knowing some more details of you car...
What is the year of your car?
Does it have cat?
I would "put my money" on conections or sensors problems...
I dont think that those problems have anything to do with the changing the central muffler...
If your car is a 1993/4 car, with cat, its possible that the Lambda probe isn´t working...
Have you tried the Portuguese Alfisti Comunity?

http://pub83.ezboard.com/balfisti

Regards

Carlos Oliveira

Chris Notsis · Posted: Thu May 12, 2005 11:21 am Post subject: VIbration and cut-out

It sounds like there may be an air leak in the system since the replacement. Is it possible that something has been cracked (at the engine pipe end where the manifold is bolted) or the O2 sensor has been dislodged or broken? Something else may be a cause: collapsed substrate in the catalyzer itself. You mention engine failure when turning etc. THis would happen if a piece of substrate or other material ( you mention the muffler was rotten - then so would other bits in the system) falls across the exhaust stream in the pipe, causing it to block air flow. Result: engine shut-down due to strangulation. One way is to tap (bottom fist is best!) the pipe along its length and listen for loose objects in the pipe.
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Chris Notsis

Bellamachinna · Posted: Fri May 13, 2005 3:42 pm Post subject:

Hi all

My car is an boxer 16v QV from 12/91 (manufacturing date). It was registered in 2/92 and doesnt have cat (so no lambda sensor).
The car starts first time, but when driving it, and if Rpm drops, stalls.
When i start it again, the rpm idle is completly crazy going from 1000/1100/900/800 and then stalls again. This hapens every time, but if i give it a throtlle blip (STRONG THROTLLE BLIP), it settles in 1000 rpm.
Of course that this is annoying, especially when engine is cold.
BUT it happens also when engine is warm....!!!!!

Help please

J.Oliveira
_________________
All'interno della mia macchina, vi sedete, tenete sopra e CHIUDETE IN SU...

alfafan · Posted: Fri May 13, 2005 4:12 pm Post subject:

As I said, I think its an electric problem.
Check the throtle switch/potenciometer connection and position...

Regards

Carlos Oliveira

Chris Notsis · Posted: Thu May 26, 2005 3:06 pm Post subject: stalling

Since it's worse when cold, but settles when revved hard, it is, as Carlos says, a likely electrical / electronic problem. Cold running problems can be due to something as simple as the coolant temperature sensor and its wiring / connectors. In fact, check all electrical connections related to the EFI - for corrosion, breakage, wear or looseness. Remove these variables and you will then have to start looking at actual systems. Not likely to be programming faults in the ECU. Check also for vacuum leaks.
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Chris Notsis