1993 Volvo 850 doesn't start (Resolved)

[hcampan]

Ok, guys, let me tell you first that you were of great help since I've started putting my hands on this newly bought car. I did find on this forum great tutorials for changing parts.

This said, I'm writing today as I'm out of clues.

Car is :
Volvo 850 of 1993, 2.0 l engine.
350 000 kms

I've changed :
Fuel filter (car was used for months without a cap on the fuel tank, bought one)
Spark plugs (One spark plug that was carboned (black), cylinder 4 from left to right).

Problem :
Car won't start, even with a spare battery.
It cranks ok.
Fuel pump does work.
Fuel pressure stays on (no leaking injector)
One spacer (little black rubber disc) lacks on injector 5 from left to right. Still the engine if I succeed to start it runs great.

What happens :
I turn the key, fuel pump runs in the back of the car and a similar noise does the same in front of the engine (looks like a mini pump ?). A flush noise comes from the little bottle in the middle of the fuel ramp.

I then turn the key full twist. The engine cranks, turn for ever with nothing else happening. I have tried many different positions on the gas pedal. No difference.

Yesterday, after many tries, I dropped the fuel ramp, popped out the injectors, put everything back in and changed the spark plug. The engine started first try ! Weather was warm same as today. The only thing was that when I did put some gas, there was some latency to respond if I did push the pedal quickly. All was fine if I pushed the pedal gently.

I made the engine run for half hour and left it until this morning when it didn't start.

I am not professional and my knowledge comes from trying. And here, I don't know what else to try.

I read it could be the fuel pump relay (marked 103) but first, I don't know where it is, and second, the fuel pump does work. And the relay seems to do a "click" at approx the same time the fuel pump stops.

Voila.

Please throw your ideas at me if you have any. That will may be help. And I'll give you every feedback I can !

Have a very nice day.

Cheers

Hubert

[turbotim2]

The relay you speak of in under the fuse panel cover under the hood. It sounds like maybe your pump isn't pushing full pressure, despite the pump running. Try to check the pressure at the fuel rail if you can.

[hcampan]

> turbotim2
Thanks for your prompt reply. And for the relay location.
Pressure check on the tire like valve on the right side of the fuel ramp. I depressed it and fuel came out with some pressure. I did it engine not running.

But !... Appart from that,

I've just started it. It was around 16 C this morning and now it is 25 C. The volvo is standing under the sun. And it started with a nearly empty battery. How strange !

But I still have the a lack of respons, or big respons time if you prefer, when I hit the gas pedal quickly. The engine nearly stalls if I don't release the pedal and let the engine grow his throttle gently.

Could that be the MAF ?

Hubert

[turbotim2]

That is sounding like the MAF now that you mention it. I have not had trouble or experience with that component so maybe someone will chime in with better advice on that. Just curious - how has the temperature outside affected the issue?

[hcampan]

Ok, while the engine was running I took the MAF out. The engine stalled.
I decided cleaning it. And broke it. Oups ! Even if I was very very careful it took a very little pressure to break the little blade.

I'm looking for one now.

And the engine does not stand idel now.

I'm feeling I'm near a solution... hope so.

Cheers

Hubert

[goober4321]

If you do a search ....a MAF from a cavalier 2,8L will work.....same hookup etc.....Anyone jump in here if I am mistaken but I did read it somewhere. As well I read that a fuel pump from a V6 Aerostar is a 1/4 of the price of one for a Volvo. It is a fraction smaller in barrel width but does fit in nicely as well with the same hookup.

[drew525]

If you determine the MAF isn't your problem, I would definitely suspect the fuel pump. It seems like it is supplying enough pressure for the car to start and idle but may drop the pressure during acceleration. I had a similar problem and even though I had some pressure at the rail the pump still turned out to be causing the issue. Just something to check.

[hcampan]

One used MAF is snailmailed to me from your nice country (US). I'll keep you updated as soon as I get it.

> goober4321
Thanks for the input. But finding those cars in France is near to impossible. Even spare parts for Volvo are difficult to find. French people prefer French cars. That's why.

> drew525
Yes you seem right. It will be my next hint. But what prevented me from doing it upfront was that throttle can go very high if you take time to wait for the throttle to catch up with the pressure you put on the pedal. So it would mean enough fuel (pressure) comes in for the engine (?). And if I recall, it has been changed with a new one 3 years ago from the invoices given with the car.

I'm a bit fed up with changing parts not involved in the problem. On the other hand, it will be done, and those parts will not break in the near future.

Next episode, waiting for my USPS parcel and open it like a gift, hopping it will work out.

Cheers

Hubert

[hcampan]

Hi there !

So, MAF is changed. No more MAF code. Engine runs better but not that good. I get power drops when pushing the throttle too quickly.

And the car won't start in cold weather (10

[turbotim2]

So when you said you were testing the relay, it took 7 seconds for the pump to shut off once pressure was achieved? That seems like a long time to me. I believe it should be more like 2 or 3. I think you fixed one problem with the MAF but have a second one involving the pump or your fuel delivery at some point. It sounds like the pump isn't building enough pressure or you have a leak somewhere such that you are losing pressure. Just an idea??