'96 Stall coming to a stop then no start Topic is solved

[magna224]

The background. Lately I have been doing quite a lot of work on my car. It has been a little harder to start than usual the past few months. It will crank usually at least 5 times then reluctantly wake up. This volvo was always a little slower to start than my old 850. I had figured it was fuel related so a few months back I put all new seals on the fuel rail and rebuilt and cleaned my injectors and threw on a new fuel pressure regulator and fuel filter. This didn't really solve anything. Before that around the beginning of the year I was doing some major maintenance and while doing it I put on new wires, plugs, distributor, rotor and did an oil change with some fresh mobil 1 10w30. During that maintenance fest I also put a new radiator and water pump which were both leaking and fresh coolant and bought a silicone intercooler/intake kit and put those on but a lot of the small lines are still old. The PCV system was serviced about 3 years ago but I did neglect to take care of the PTC. I don't know if it may be involved but my tachometer has never worked right for many years. Idling it sits at 0 it seems to be about 1000 RPM off at all times. I have never really cared that it was off but I figure its good to disclose in case it could be related.

Now on to the bad stuff. My car was feeling a little sluggish on my way to visit my family a few weeks back. I was going probably about 50 down an empty road and the light up ahead was red so I started to brake and as I slowed to a stop my car went still and silent and had the christmas dash. Pulled the key from the ignition, put it back in, and attempted to start it. Just the usual long attempt I had become accustom to but no actual start. Another attempt or two were made. Now stuck in traffic with the light about to turn I violently began doing the shifter row for the remainder of the light. Still nothing. Pushed it off the road and towed it to my parents. There I found quite a few vacuum leaks in the EVAP/EGR system which I fixed. Disconnected battery and cleaned idle air valve the throttle body was cleaned at the end of last year. I also replaced the fuel pump relay and noticed my ECT and thermostat (which I hadn't ever replaced) were not OEM so they were both replaced. After all this the car starts but runs really rough and stalls after a 5-10 seconds of running very poorly. Giving it gas doesn't seem to really do much. It drives maybe 15 foot before it stalls. When it was idling and I unplugged the MAF it died instantly. I'm not sure if that is supposed to happen. I actually have a MAF and fuel pump insert in the mail. All of these parts I planned on replacing this year anyways so I don't mind throwing the parts cannon here. I'm out of the things I actually want to replace though so I had better get to actual diagnosing.

Does anyone have any ideas about what may be going on here?

[abscate]

Pull the plugs and look at them for a diagnostic of running. Thhen compression test to check valves and rings.

A big vacuum leak could be the culprit here, too. That needs the famous drea dead task of removing each and every hose, evaluating, and replacing. Unglamorous, but necessary

[rspi]

Probably the fuel pump went out. Sometimes they slowly die, reducing performance, causing hard starts, long cranking, then finally die.

Seems like most die between 150,000 to 200,000 miles. They are electric and do wear out.

[rguzz]

Hard cranking before total failure does provide clue to possible fuel pump failure. Fuel pressure testing sooner than later may avoid un-necessary $$ spent and direct you straight to the problem. You may hope that's the problem, simplifies a potentially time consuming search. Otherwise, suggestions noted above.

[jimmy57]

A 95-96 850 non-turbo often has two speed fuel pump system. Mot 4.3 uses this, Mot 4.4 doesn't. The pump relay has two outputs, one direct to pump for above 3000 rpm and the other is output that goes to the resistor that is mounted in the cowl next to HVAC fresh air fan inlet on RH side on LHD models. The resistor runs pump slower at lower revs to reduce fuel churning as the extra fuel vapors. This is the precursor to the fuel pressure sensor full time variable speed fuel pump system that regulates fuel pump current (and thus speed) to control fuel pressure.

The relay may not be switching on the low speed output or the resistor is unplugged or defective. Or the pump is bad as mentioned and the higher speed output was making it run and now it doesn't. Quick test is to find the fuel pump wire aft of RR seat, it is pink and becomes red at a connector in that area. The wire is heavier gauge than the other wires around. Probe for voltage while cranking. If pump is bad it likely will have really low voltage due to the loading on the resistor when pump is stalled. You can go high tech and have someone crank it over while you kick the RH side of tank from underneath to see if you can jolt pump int running (probably for one last time).

[magna224]

Pull the plugs and look at them for a diagnostic of running. Thhen compression test to check valves and rings.

A big vacuum leak could be the culprit here, too. That needs the famous drea dead task of removing each and every hose, evaluating, and replacing. Unglamorous, but necessary

I have been thinking of attempting a home made smoke test. When my car stalled out coming to a stop it happened to be the first drive after I filled up my gas tank this led me to believe it was EVAP related. I forgot to mention that. Upon inspection of the system the rubber joint before purge valve was cracked on both ends and probably had a significant leak. A hard black vacuum line that was zip tied to the fuel line a little north of the fuel filter was completley disconnected at a joint in the middle of the car. The third major leak (which I may actually have pulled loose at some point) was whatever that odd thing under the battery tray is where one line goes in and has some lines that go from and back into itself and it looks like it has a valve or vent on it was disconnected too.

Probably the fuel pump went out. Sometimes they slowly die, reducing performance, causing hard starts, long cranking, then finally die.

Seems like most die between 150,000 to 200,000 miles. They are electric and do wear out.

My car is just getting to 150k so still young but it is getting very needy. My old volvo when its fuel pump went out had a little bit slower starts for 2 weeks then just stopped working completely one of those days. I had ordered the hella pump Monday and am hoping its a decent alternative to OEM. Someone told me its very similar to the walbro I've heard decent things about. So I just bought it on a whim. Usually buy OEM or something I know has proven better but didn't see one for under $100 and was in a rush leaving for work. Really for the price if it lasts until my next PCV service I'll be happy. Are the volvo 850 headlights hella? I noticed mine are. Is that stock?

Hard cranking before total failure does provide clue to possible fuel pump failure. Fuel pressure testing sooner than later may avoid un-necessary $$ spent and direct you straight to the problem. You may hope that's the problem, simplifies a potentially time consuming search. Otherwise, suggestions noted above.

Good to know a few people are thinking fuel pump and I hope so since ones on the way regardless. I've been weary of a fuel issue for a long time. I was thinking of getting a fuel pressure gauge because it could be helpful in many future explorations but I never even went and looked. My pump still makes noise but maybe it has just enough power left in it to prime it and start but cant sustain it. My dad seems to think its fuel related too. I've been chasing the EVAP theory which is still fuel related in a way.

[rspi]

Yes Hella makes a lot of parts for Volvo.

My daughter's S70 recently experienced fuel pump failure. When she replaced it, she noticed a gain in the performance of the car.

My buddy Buster Brown was having long cranks last week on one of his 850's. Poor performance and high fuel consumption. Replaced the fuel pump and all is now well. His fuel pump unit actually had a split in the hose above between the pump and bottom of the cap.

[magna224]

This is that thing I was trying to explain under the battery box. That is what was disconnected.





This was the old line I was talking about by the fuel filter that was completely disconnected too. You can see the old one to the right that was sitting like that with only one side even in.







And.... Oh, yes...... That connector is in tact too before anyone says it.

[magna224]

Yes Hella makes a lot of parts for Volvo.

My daughter's S70 recently experienced fuel pump failure. When she replaced it, she noticed a gain in the performance of the car.

My buddy Buster Brown was having long cranks last week on one of his 850's. Poor performance and high fuel consumption. Replaced the fuel pump and all is now well. His fuel pump unit actually had a split in the hose above between the pump and bottom of the cap.

Wow! It sounds like everyone needs a new fuel pump. #1 step of stage 0? Your car can run with a coolant, small air, or oil leak but it cant without a fuel pump!

[jimmy57]

The thing bellow batt is the ruise control vac pump/regulator and has a vent port open on purpose.