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Discussion Starter #1 (Edited)
Hi,
I experienced the following problem today. The car was already hot and I had to stop for a few minutes. When I started it again everything seemed fine but when I tried to accelerate it had no power. It would not rev past 2000 rpm. No power at all...it was struggling up a hill. I decided to stop, pulled the handbrake and waited for a minute without turning off the engine. After 1 minute I tried to accelerate and everything was fine. When the problem occurred there was a beeping from the computer but no warning light. As soon as I got back home I used my diagnostic equipment to check the faults in the ecu...surprisingly there were none...
Any ideas what's wrong?

Alfa 147 1.6 TS
 

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Blocked cat/ exhaust maybe? The best way to check this is to bolt the exhaust off at the manifold and take it for a noisey run, make sure you do this at a sociable hour though :)
 

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All I can possibly think of is a loose connection on an injector or a temporary fuel blockage that has thrown the ECU into limp home mode... Although I would have thought that at least some record of the the fault would be there when running the diag. Some cars don't though:rolleyes:

Check the connectors and give it a nice fuel treatment as a preventitive measure. Redex or any propriety stuff will do. ;)
 

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Discussion Starter #4
Blocked cat/ exhaust maybe? The best way to check this is to bolt the exhaust off at the manifold and take it for a noisey run, make sure you do this at a sociable hour though :)
The cat has been removed so this is not the problem.
What do you think about the MAF?
 

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The cat has been removed so this is not the problem.
What do you think about the MAF?
I'm not too familiar with these to be honest with you but there are a few threads on these already which suggest you disconnet it and go for a test drive.
 

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Discussion Starter #7
I'm not too familiar with these to be honest with you but there are a few threads on these already which suggest you disconnet it and go for a test drive.
Apart from that problem the car runs fine...so I do not expect any change when I disconnect the maf....
 

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Discussion Starter #9
+ 1 .... my thoughts too
I think that a fault in the crank sensor will be registered in the ECU...what do you think? There were no faults in the ECU though there was a continuous beeping sound from the computer during the problem. These beeps made me think there would be faults in the ECU...however there was nothing...
 

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I think that a fault in the crank sensor will be registered in the ECU...what do you think? There were no faults in the ECU though there was a continuous beeping sound from the computer during the problem. These beeps made me think there would be faults in the ECU...however there was nothing...
Well to be honest... No... On many other manufacturer's the CPS does'nt throw up any ODB faults... At least it didn't on my Citroen C5 when it played up with a Siemens ECU (quite popular on all euro cars)

I can see why many would think it would be CPS related but as you have already stated... the car would start up and run. CPS when it is hot and faulty typically won't start until it is cooled down (about 30 mins or so)....
I wouldn't discount the fact that it could be CPS related but if it is, then it is in the very early stages of failure. If that is the case, then wait and see if it re-occurs or gets worse to the point of refusing to start first... Then you will know for sure m8.

At the moment I would still tend to think it was fueling related by your discription and your actions during the fault.
 

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It seems that nobody thinks it could be a faulty MAF...
It maybe because as you have already said that there was no fault codes m8 to lead it to being a faulty MAF... The usually do throw a few up on Diag.

If the car is running right, then it's highly unlikely to be the MAF, they don't cure themselves, they just get worse.
Many, many owners get a "phobia" or "hang-ups" about the dreaded MAF issues... :rolleyes:
In reality.... They often change them based on advice from others (not their money they are wasting) when quite often, a good clean of the plug contacts or at worse, cleaning the MAF itself would suffice... 20 minutes worth of your time or £120.00+ for a new part. I know what I would try first:thumbs: After all, of course it does the trick... It should do as it's a new part! Yet they don't actually try cleaning the old MAF and trying it back on... DOH!
Don't worry about the MAF just yet m8:)
 

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i had a faulty crank sensor it didnt put up any fault codes and caused a missfire so in my experience they can be weird and tempramental things
 

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I'm ruling out the crank sensor, the engine kept running, if it had failed then it would have cut out and not restarted for about 30 minutes if at all. Also every other sensor, except the water temp sensor, if that lied to the ECU, you wouldn't get a code, but you would get a loss of power as it threw a hot engine into the start up mode (choke on), which would flood the engine giving inefficient brn and huge loss of power, until it had burnt off the excess and the sensor had sorted it's life out.

Check the wiring from the grey plug on the thermostat housing and trace the wiring looking for shorts/breaks.

Also check your battery terminals are tight.
 

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my faulty crank sensor never made the car cut out just a misfire from cold its only a sugestion but i dont think they are as simple as cut out for a while when hot in my opinion they can behave in different ways when faulty
 

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Discussion Starter #16 (Edited)
The engine kept running without any problems. It was only when I tried to move the car that I experienced the problem. It was hard to move it at all. I would say it looked like a misfire. I have experienced a misfire in the past but it threw a fault in the ecu and the engine management light was on all the time.
 

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Discussion Starter #17
my faulty crank sensor never made the car cut out just a misfire from cold its only a sugestion but i dont think they are as simple as cut out for a while when hot in my opinion they can behave in different ways when faulty
Did you have any faults stored in the ECU?
 
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