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100% Fuel pressure regulator. I went through this exact same thing. Not anything easy to look at to determine if it’s working correctly. I replaced mine and it was exactly why after my car stalled and wouldn’t start again. The FPR is supposed to pull the fuel back when the car stops running and instead fuel was being dumped into the engine. It was like the car was flooded and it wouldn’t start. 30 seconds or so later it would start. Pretty annoying at a stop sign with cars behind me!
Isn't the FPR supposed to do the opposite? Make sure the Fuel pressure remains at the Fuel rails even when the car is shut off?
Ok, found the ISV, thanks. Could not find, via search, a service manual, though. Do you have a link?
Also, the two hoses are attached with crimp on clamps. I'm going to try and pry them off with a screwdrivef and reclamp them but will probably have to cut them off. Then I'll have to figure out the diameter for a replacement clamp.
So, it was easy for me to find ISV but not so easy for me to remove it. I'm just a novice though.
You can see from the replies the various and different pointers for the same symptoms. Case of methodically going through possible causes and seeing what works (starting with easiest/cheapest). Cleaning the ISV is low hanging fruit - try not to damage the hoses. Jubilee hose clips/clamps easy to find and cheap (16mm-22mm I think) - stainless ideal. Once off, check for built up deposit and simply clean/flush through with a can of carb cleaner and lint free cloth. Next up maybe try swapping out the DME relay (R41) and see if anything improves. Then go on from there... good luck!
Isn't the FPR supposed to do the opposite? Make sure the Fuel pressure remains at the Fuel rails even when the car is shut off?
Could be. I should have noted that I have zero mechanical knowledge. I do know that the part inside the FPR that had some flexibility characteristics in order to work properly and didnt work anymore. So if it was supposed to push, pull or hold fuel, it wasnt doing that. For me it would stall, Id crank for ever and it wouldnt turn over. It was way worse when the engine was hot. If I waited for a couple or more minutes it would start right up. After replacing the FPR it never happened again. My car still stalls (light weight flywheel) but now fires right up when it stalls.
Do you push in the clutch when you come to a stop?
I tried pushing in the clutch while coasting to a stop and occasionally tapping on the accelerator. That didn't help.
For years I've had a similar situation happen when I had the AC on. The car would stall coming to a s stop. Putting it in neutral from 2nd gear when stopping and occasionally tapping the accelerator would keep it from stalling. The big difference was I could restart it immediately. With my current problem I have to wait quite a few seconds before attempting to start. If trying too early it would act like it was flooded.
100% Fuel pressure regulator. I went through this exact same thing. Not anything easy to look at to determine if its working correctly. I replaced mine and it was exactly why after my car stalled and wouldnt start again. The FPR is supposed to pull the fuel back when the car stops running and instead fuel was being dumped into the engine. It was like the car was flooded and it wouldnt start. 30 seconds or so later it would start. Pretty annoying at a stop sign with cars behind me!
Got the car back from the mechanic. The problem was the distributor belt broke and causing the fuel to flood. That's why I had to wait a minute or two before it would start again.
Got the car back from the mechanic. The problem was the distributor belt broke and causing the fuel to flood. That's why I had to wait a minute or two before it would start again.
I am sorry but that doesn't make sense to me. The distributor belt drives the second distributor which fires the second set of spark plugs. With a broken distributor belt your primary set of spark plugs still fire so I don't see how you get pooling fuel. The real issue with a broken distributor belt is that the secondary rotor no longer moves and if you are unlucky it will fire the same spark plug all the time which causes significant misfires and possible engine damage.
Excessive fuel in the intake can point to a bad FPR when you get fuel dumped through the vacuum line. As stated before, an easy test. Just pull the vacuum line and see if you get fuel.
I am sorry but that doesn't make sense to me. The distributor belt drives the second distributor which fires the second set of spark plugs. With a broken distributor belt your primary set of spark plugs still fire so I don't see how you get pooling fuel. The real issue with a broken distributor belt is that the secondary rotor no longer moves and if you are unlucky it will fire the same spark plug all the time which causes significant misfires and possible engine damage.
Excessive fuel in the intake can point to a bad FPR when you get fuel dumped through the vacuum line. As stated before, an easy test. Just pull the vacuum line and see if you get fuel.
Interesting. Just relaying what my mechanic stated to me. Wish I had time to learn exactly how everything is functioning.. And the time to do something about the problems. Just had my hip surgery so there was no way I could work on it.
Is there any doc or tutorial I could obtain to explain how the 964 engine and power train work? Hopeful, in a month or two I can be more fully engaged with repairs.
Interesting. Just relaying what my mechanic stated to me. Wish I had time to learn exactly how everything is functioning.. And the time to do something about the problems. Just had my hip surgery so there was no way I could work on it.
Is there any doc or tutorial I could obtain to explain how the 964 engine and power train work? Hopeful, in a month or two I can be more fully engaged with repairs.
Agree with cjoenck, the mechanic explanation doesn't hold fully - unless he's describing or interpreting something else. The below screenshot might help; twin distributors - one taking it's drive directly from the engine, the other being driven by a small belt (not shown in the diag) from that driven primary distributor. If the belt were to break then the secondary dizzy rotor arm would become stationary and may be stuck at a point of a constant spark being generated - not good! However, highly likely is you'll know something up pretty quickly with very constant rough or flat ignition etc.. Hope this helps visualize.
Interesting. Just relaying what my mechanic stated to me. Wish I had time to learn exactly how everything is functioning.. And the time to do something about the problems. Just had my hip surgery so there was no way I could work on it.
Is there any doc or tutorial I could obtain to explain how the 964 engine and power train work? Hopeful, in a month or two I can be more fully engaged with repairs.
The book by Adrian Streather is considered a classic and a great reference for the 964. It's available online at the big retailer. I would start there. This forum has covered every conceivable project in detail. Search is your friend.
Agree with cjoenck, the mechanic explanation doesn't hold fully - unless he's describing or interpreting something else. The below screenshot might help; twin distributors - one taking it's drive directly from the engine, the other being driven by a small belt (not shown in the diag) from that driven primary distributor. If the belt were to break then the secondary dizzy rotor arm would become stationary and may be stuck at a point of a constant spark being generated - not good! However, highly likely is you'll know something up pretty quickly with very constant rough or flat ignition etc.. Hope this helps visualize.
That helps a lot. Thanks for your response. I couldn't see how a distributor could cause fuel flooding... And I still don't. But, then, I still don't understand the purpose of the 2nd distributor. Would it cause a spark plug to not fire and thus fuel would accumulate in that cylinder? If that's true then why would it stall only when I'm coming to a stop and not during driving?
So, I agree with you gents and need a better explanation from my mechanic. Sadly, because of my hip surgery last Thursday I can't drive the car to see if it fixed my problem or not.
Alfa Romeo pioneered the use of twin plug/spark engines (way back in early 1900's I believe, then on their later race cars). Provides more power and fuel burn efficiency. To answer your question; yes, a broken drive belt (to the secondary distributor) would cause a spark plug, fed from that distributor, to not receive its HT current for a spark. However, no, fuel under correct pressure or metering would not accumulate in that cylinder - fuel continues to be ignited by the other spark plug in that cylinder head.
As mentioned earlier your issue should focus more attention on the fuel supply (or oversupply?) in this instance. The fuel supply system has many components to it (from the tank itself to the injector and often forgotten; the charcoal canister fuel evaporative system). I can't see where you've mentioned any swap out of the DME fuel relay, as a cheap easy starter. Fuel pressure regulator already mentioned a wise inspection (others may chime in to confirm if this can be bench tested for a fault). May be prudent just to change this anyway.
Agree 100% cjoenck - get yourself a copy of Adrian Streather's 964 bible and while you're resting up and your mechanic is fumbling around you'll discover so many new things about your 964 you never knew (puts so much in perspective). Hope this helps..
Is there any doc or tutorial I could obtain to explain how the 964 engine and power train work? Hopeful, in a month or two I can be more fully engaged with repairs.
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