940 stall after driving shortly

ill list the following parts recently changed and we can go from there:

head gasket
new/used 15g turbo put on
mani ported
timing belt
coolant temp sensor
intake mani gasket
valve cover gasket
plugs
wires
cap
rotor
all vacc lines
most fuel lines(couple left but seems ok)
removed charcoal canister
removed cruise control(was broken anyways)



that was about the long and skinny of replacing the head gasket and putting the 15g on
so after i got done with that all was well...for a bit.
Drove for about a day then started to sputter and idle low, give it gas and no power sputter and pop then stall, but it would start back up, finally it stalled and wouldnt start for around an hour. I had it towed home and thought the crank position sensor is the culprit, came in the mail today installed it and idled fine all was good i thought till about 5 min of driving it started the sputter again,lack of power almost like it is not running on all cylinders, stalled down the road far enough i had to have it towed...again.

So im just about done ****ing with this damn car as i need a daily driver and its been a piece of lawn furniture for about a month now, any ideas as to whats causing my problems?

My ideas are as follows:

Fuel pump buzzes every turn of the key so i am not thinking thats it.

Possible clogging or clogged fuel pump? would explain why after it sits for a day it starts and idles fine till i drive it and give it gas

coil issue maybe?

do 940's with LH 2.4 have radio supression relays? if so where are they?

im just about out of ideas and patience and need some help desperately, else i have to take it to a shop and pay out the ass to fix it which i really dont want to do...

Thanks in advance turbobricks keep the brick alive!

I do not think the symptoms fit a defective radio suppression relay, but it deserves a look:

<a href="http://s50.photobucket.com/albums/f325/rstarkie/volvo/?action=view&current=rsr.jpg" target="_blank"><img src="http://i50.photobucket.com/albums/f325/rstarkie/volvo/rsr.jpg" border="0" alt="Photobucket"></a>

While the symptoms don't seem right for the ignition amplifier I would swap a known good one in just to be sure. You do not even need to unscrew it from the drivers inner fender- just unplug the connector and plug it into the known good one. My experience with amplifiers is that the car simply dies without sputters or misses- only to restart and do the same thing again after it cools for a short time

Good luck
Randy

Maybe intake gasket?

I'll bet some sort of vac leak. Any check engine codes?

I am thinking some kind of vacuum leak also. The smallest leak seems to cause all kinds of odd issues with these cars.

well when it does start it idles perfectly fine and hold steady vacuum at around -20 or so if i remember right same as it always did, and if it was a leak why would it start and drive fine shortly then act up if it was a leak i would imagine it would be a persistant problem yeah?

i think the battery is dead atm so ill jump it and get codes tomorrow

also will try the ignition amp tomorrow, will head to the junk yard and pull some and try it out any more ideas are appreciated!

Fuel pump relay, power stage, radio relay are all suspect. You need to first check for spark when car won't start. Timing light is safest. Tonight I checked spark at coil by unplugging it and holding wire close to terminal while buddy cranked. Or get a remote starter switch.

Too much to type on mobile. Check my recent thread in maintenance and check brickboardfaq FAQ.

power stage and radio relay are my ideal culprits also i tried 5 diffrent fuel pump relays 2 known working ones and no change ive had these go out on me before and i know how they act =)
thanks for the input

Like I said check for spark when it's dead. If u have spark, pull the fuel rail and reground the wires and crank engine and check for fuel spray. That will check injector pulsing and an idea if your fuel pressure is ok. Or plug in noid light from IPD and check for flashing or ug in spare injector and feel for clicking. If you have spark and injectors firing check fuel pressure. Good luck and post back with results!

edit: nm i found the powerstage but all were gone at one pnp will try another tomorrow seeing if the RSR is the culprit today but its rather chilly out and rainy not really wanting to go work on the car in 35 degree rain =P

A bad radio suppression relay will cause these problems. When the contacts get corroded/burned, the resistance goes way up. High resistance = a lot of heat produced. As heat goes up, so does resistance. IOW, the car will start and run fairly well. Then, as the contacts heat up, the power to the injectors drops resulting in a lean condition. Eventually, there isn't enough power to open the injectors and the car dies. The relay cools off, the process starts all over again. It makes diagnostics a whole lot of fun.

when was the last time you changed the fuel filter.

35 degree rain in west palm?????

Massive airleaks can also cause stumbling and stalling.

Have you tested for spark yet when it's dead?

tried a couple other RSR's seem to no avail, power stage is my next try, my car is at my gfs house and my tools are limited so im just pulling easy parts to try and then going from there...anyway to check the resistance on a RSR to see if its good? took me 20 min to find mine since it was not on the strut tower and laying down almost on the side of the battery and down on the bottom...

Just pull the radio supression relay and use a piece of wire to make a connection between the two heaviest wires in the plug. With that wire as a jumper if it starts then the relay is at fault for a no start when it is in place.

Randy

Wear a rubber glove and dont touch the car and pull the ignition wire off the ignition coil and have your gf crank the engine. If you see a crisp CONSTANT spark you know the ign is good.

Did we already suggest the crank sensor? That is almost the first thing you should check. Wiggle the wires while gf cranks and see if it starts.

stasis said:

tried a couple other RSR's seem to no avail, power stage is my next try, my car is at my gfs house and my tools are limited so im just pulling easy parts to try and then going from there...anyway to check the resistance on a RSR to see if its good? took me 20 min to find mine since it was not on the strut tower and laying down almost on the side of the battery and down on the bottom...

Click to expand...

Yes. Put 12V across the coil connections of the relay to energize it, check the resistance across the other 2 terminals with an ohmmeter. It should be less than 1 ohms if it is in good shape.

brand new crank position sensor, so i know thats not it...will check rsr tomorrow. any chance its the power stage? just trying to get input payday is thursday and then ill go to town for one last time then takeing it to a shop

stasis said:

brand new crank position sensor, so i know thats not it...will check rsr tomorrow. any chance its the power stage? just trying to get input payday is thursday and then ill go to town for one last time then takeing it to a shop

Click to expand...

I have never had a powerstage cause these problems, however, a friend of mine that has a Volvo repair business has. The car was a 1991 940 SE. Not that the model matters at all. It would run fine, then wouldn't run at all, yet, if you checked it, the car had spark. The ECU, ICU, crank sensor, injectors and on and on were replaced with know good parts, yet, the problems continued. The car finally got parted out due to the electrical gremlins. The powerstage was put on another car and low and behold, all the symptoms the SE had followed the powerstage to the 93 940 it was installed on. I certainly wouldn't rule out the powerstage as being the culprit on your car.

thanks for the input went to a new local jy today and noticed that EVERY power stage was removed from the 7's and 9's that were there made me think for a minute...someone came and knew what they were looking for since the ecu and ezk were also missing from every turbo model and other good easy small parts were also missing but at the other local pnp noticed all the power stages intact maybe someone local had the saem problem?
anyway thanks again for the information i really hope it is the power stage local volvo dealership charges 135/hr for labor and im not wanting to pay that but i love my 940 and will pay if i have to

Have you done the wiggle test to the RPM sensor wiring yet?

Dont pay Volvo a penny. Do it yourself! Powerstage is two bolts and RPM sensor is one bolt.