Hi all,

I'm working on a friends 850, and he tells me for the past 2 weeks his car has been having some trouble.

First off, trying to start, it cranks and is hard to start. It gets worst as the engine warms up.

Had a check engine light and brought it to oreily to get the codes pulled.

It has a P0440 (evap) and a P0172 too rich on bank1.

Also, if that wasn't enough, sometimes after he start the car, it won't come off park, he needs to press a button next to the shifter. At that point, his turn signals don't work and neither does his spedometer.

Any advice would be greatly appriciated.

 

Is the car turbo? If so, it likely has some vacuum issues. Also, what year is it?

Hard starting can be several things from low fuel pressure to a bad ECT (engine coolant temperature sensor, which usually has it's own code).

 

 

 

Rspi, You're Awesome!

It's a non turbo 96.

I'll check out the videos.

Thanks again

 

Try to imagine I don't know your friend. I've never been given a ride in it or even seen his car. NOW, try to tell me what it is. Telling me it's an 850 is the same as saying he has a girlfriend. It doesn't say how pretty, smart ....
Tell us what you can about the 850 as they aren't all the same.

As for running rich one thing to do would be to pull the vac line to the fuel pressure regulator if you have one up on the fuel rail and see if there is fuel in the vacuum line of if fuel drips from the nipple of the fuel pressure regulator. If the diaphragm inside is ripped it allows the engine to suck in fuel and will drive the engine rich.

Also, if you have to replace it always replace the short (2-3") return line. Make sure you use fuel injection fuel line and not the lower pressure, lower cost carburetor application fuel line.

 

The '96 models have an air pump system to assist with cold starts. Google that code and see if there is a way to clean up a valve that is part of the system and make sure the vacuum lines are good (especially the elbow connections).

 

Hey KissAFrog,

My apologies, I know very little about Volvos. I've worked on just about every other car.

This is an 1996 850 non turbo 2.4L. It has a hard start problem that's worst when the engine is hot, and the 2 codes I mentioned above P0174 and P0440.

I'll have him look at the pressure regulator

 

Hard starting issues are usually the ECT or a fuel pressure issue. The ECT will usually toss a code so the problem is likely low fuel pressure, vacuum leak or the purge valve.

 

Thank you RSPI, what should the pressure be on a 96 2.4L?

 

All of the white blocks should be around 43 psi I think. Maybe the fuel filter is a little clogged but seeing your code Kiss is likely pointing you in the right direction.

 

Ok, pulled the vacuum hose from the pressure regulator and no fuel in it. no brakes in that vacuum hose.

fuel pressure is 43 at prime but drops down to 33 when running. I'm going to replace the fuel filter.

My buddy dindn't hear the air pump running this morning any quick way to test it?

What's the next recommended course of action?

 

ok, looking at the photos for where the air comes in for the air pump and the SAS, and noticed, this vehicle does not come with an air pump.

 

Cool. Hopefully the fuel filter change will help.

 

Thank you. Unfortunately the filter change did not help. But boy was it old. We did discover a cut line just behind the fuel filter. We repaired it. Both side connected to a solenoid or something.

Unfortunately that didn't help either. We're still having a hard time starting it, Sometimes.

We unplugged the battery but are still getting both error codes.

Any ideas where to go from here?

 

The reason for the fuel pressure regulator having a vacuum line is that under higher vacuum (idle) the regulator lowers the pressure and when under no vacuum like wide open throttle the regulator raises the pressure as more fuel is needed.

If you have a gauge connected, engine running and you pull the vacuum line off you should see the pressure rise. If not, it's bad.

It could be the regulator not holding pressure or for the hard start there is also a check valve in the fuel pump and once it runs for a couple seconds when you first try to start it, that check valve is supposed to hold that prime or pressure.

 

Looks like the fuel pressure regulator is fine. Primes at 44, idles at 34 and when I disconnect the vacuum, it goes up to 44.

At start up it stays at 44 even when we're having trouble starting.

What I noticed, is when the problem occurs then engine starts to crank normally but after the second turn, it sounds like a high speed whine. Sounds like (womp, womp, wiiiinnneee) if that makes any sense.

Any thoughts would be greatly appreciated.

 

Take a spark plug out after you cranked it. Is it wet? If yes you are getting fuel.
Check also that you have a spark. Try also with an open throttle to see if it changes behaviour.