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Discussion Starter #1 (Edited)
HI guys, I’m having problems with my old alfa romeo 145 QV.

I already changed a lot of things to try to get it fixed but don’t works.

Let me try to explain the fault.

When im driving the car and I press the accelerator pedal fast, the car don’t react, and looks likeit brake instead accelerate, looks like don’t have enough oxygen or enough fuel, my English is very bad, hope understand me 

Other thing that happen is to start the engine, I need to try it 4-5 times to get it running.


Can someone please move this post to the Alfa 145 forum? :) I dont want to duplicate the post.
 

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Without knowing what you've already checked, I'd say benzina..

Disconnect the fuel pipe where the rubber tube from the tank joins the injector rail next to the engine. Catch any spilt fuel in a rag or a small cup (the top of an aerosol can etc.) then dry it all up, so there's no petrol there.

Then turn on the ignition... and crank the engine over a few turns.

When you switch on the ignition you should get a short "pulse" of fuel.. (designed to pressurise the fuel rail) and when you crank the engine you should get a flow of fuel. If your fuel flow looks "weak" (not much petrol coming through), then the fuel pump could be the problem.

If the supply is good.. have a look at the regulator on the injector rail. It's possible to measure the pressure in the fuel rail but you need special equipment for that. It's easiest (but more expensive.. it's a gamble) just to change the regulator and see if a new one is any better.

See how you get on... but it sounds like fuel starvation to me.



Ralf S.
 

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spark plug

check spark plugs...easy job and they can cause lot of different symptoms..check that there is no water or oil in wells..also check ceramic insulation is not cracked on plugs.
 

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Discussion Starter #6
well guys, i changed Lambda, Fuel pump, sparks, Filters, checked pressure in the fuel rail (looks OK, between 2.7 and 2.9 Bar), like 3 months ago i remove the sparks cover and i found OIL in the 4th cylinder, is possible that its the problem ? maybe habe oil again, will check that this weekend!
 

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Split flexy intake pipe? The oil doesn't sound good though! Could be duff coil.
 

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Discussion Starter #8
The intake pipe are OK, i change it last week.

tomorrow will open the sparks cover to see about the oil and to see if this fi something, will try to use some kind of glue to try to fix the oil problem.
 

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Discussion Starter #9
well removed the sparks cover and found like 100cc inside the 4th cylinder, after clean it measure the cylinder pressure, and i get like 11-12 bar in each one, so looks OK.

really cant find any good way to check the coils, will still searching google to see if can find some good way.

Btw, i reassemple the sparks, and try the car again, first 2 blocks run OK, but after that, start fail again. After that removed the MAF and the car dont work anymore. Reconnect it, and run again, but still fail. Removed the MAF again, and go worst.

This night will try to clean the stepper motor to see if something go better.

Sorry for my english :)
 

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Im thinking lambda too. Check it again anyway. Also, are the lambda & MAF genuine parts or cheap ebay parts?

Get it plugged in to see what it throws up.
 

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I think plugging it is would be a good thing to do as it removes a lot of the guesswork...

If the car is an earlier Aluminium topped engine the issue could also be caused by the air temerature sensor, which plugs into the inlet near the MAF.
 

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Btw, i reassemple the sparks, and try the car again, first 2 blocks run OK, but after that, start fail again. After that removed the MAF and the car dont work anymore. Reconnect it, and run again, but still fail. Removed the MAF again, and go worst.
When you say you "remove" the MAF, did you take it right out of the car?

To test the MAF you just disconnect it (pull the electrical plug out of the MAF) but the MAF should stay where it is.


Also if the car started to fail again after you took the coils out... then we're getting close to the problem. If the spark plugs are new then the coils and leads could be causing the problem.

Take the coils out (one at a time, so you don't get the HT leads mixed up.. :D) and take the lead out of the coil. Make sure the ends are clean and dry and in good condition. They're 14 or 15 years old now and they can become corroded or burnt.

Have a good look at the coil too, when you have it in your hands, to see if there's been any arcing. You might see little grey lines on it (like a pencil).

The inside of the coil's turrets (for the leads) should also be clean and dry and the connector on top of the coil should be in good condition too.

Did you notice the injectore light flashing when the car tries to accelerate?


Ralf S.
 

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Discussion Starter #16
When you say you "remove" the MAF, did you take it right out of the car?

To test the MAF you just disconnect it (pull the electrical plug out of the MAF) but the MAF should stay where it is.


Also if the car started to fail again after you took the coils out... then we're getting close to the problem. If the spark plugs are new then the coils and leads could be causing the problem.

Take the coils out (one at a time, so you don't get the HT leads mixed up.. :D) and take the lead out of the coil. Make sure the ends are clean and dry and in good condition. They're 14 or 15 years old now and they can become corroded or burnt.

Have a good look at the coil too, when you have it in your hands, to see if there's been any arcing. You might see little grey lines on it (like a pencil).

The inside of the coil's turrets (for the leads) should also be clean and dry and the connector on top of the coil should be in good condition too.

Did you notice the injectore light flashing when the car tries to accelerate?


Ralf S.
found this in the first cylinder. (just removed the first coil one)


this looks OK, right?


this looks not good but still connected,dont think that its the problem.

where i need to find traces little grey lines?
 

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Usually arcing takes place around the "turrets" where the HT leads attach to the coil.

I've attached a picture with red lines to show what it can look like.

On the first photo, is the big grey mark just dirt or is it a scorch on the surface of the coil (looks pretty big to be a scorch mark from arcing... but it would explain the problem..).


What do the ends of the leads look like (where they plug into the coil and also where they connect on to the top of the spark plugs)? They should be a nice shiny metal. If they look white and powdery, then that's not so good..


Your cracked boot isn't great.. but as you say, it's probably not the problem. If it was wet, it might cause trouble but it looks intact for now...


Ralf S.
 

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Discussion Starter #18
well, i loose all the coils but still get it in the holes, so i start the car.

After that, start to unplug 1st one, and the motor start fail. THen reconnect it and unplug 2nd and motor start to fail. Then reconnect it and unplug 3nd, and motor not fail. then reconnect it and unplug 4th, and motor not fail again. is that normal? :S

the ends of the leads dont looks shiny, some are
 
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