Hey all,

My 1990 240 DL sedan has been running but running rich, smells like fuel when the RPMs increase, emissions increase with the RPMs. I replaced the O2 sensor and then the fuel injectors. After replacing the fuel injectors, the car will not start. It does roll over and there was initially some combustion but now it’s just turning with no combustion. We also tested the hose to the to fuel pressure regulator and there wasn’t any fuel coming out. We just replaced the main fuel pump and fuel filter but it still won’t start, even with starter fluid sprayed where the air filter is. We bench tested the old and new fuel pumps and they all worked. We also tried to test the fuel pump plugs under to see if electricity is going to the pump but it wouldn’t turn over without the pump. We know electricity is going to the spark plugs but we haven’t tested the plugs themselves to see if they’re wet. I also replaced the fuel pump relay. Anyone know what the issue could be? I’ve also been wondering how to manually prime the fuel pump so fuel rail is primed. Appreciate any input!

 

You keep replacing parts that you don't need relating to the fuel system - but have admitted/discovered that even if bypassing the fuel system (by substituting Ether for gas) the spark plugs do not fire. I suggest looking at the ignition system, and before that make sure your timing belt is still on correctly. (what's the condition of the engine speed sensor?)

Do you have a noid light to verify the injectors firing? Both the injectors and the ignition system use the signal from the speed sensor - so if you have either injector pulse or ignition pulse - the speed sensor is working ok.

$5 test light on the coil to watch the ignition pulse?

 

+1 for what Hoonk said. If it won't fire or even try on starting fluid, then you have a spark/ignition issue. Check all your connections or anything you might have disconnected or messed with when you were last working on it. Its easy to overlook or forget to re-attach an electrical connector. If everything is connected properly, check for spark coming out of the wires going to the spark plugs and go from there.

 

If you have no spark then it's most likely your crank position sensor - or engine speed sensor as Honk called it.

 

Hi Hoonk and Goldenblock. My 1993 240 wagon has resumed its n0-start issues. It has done this when hot after running for 20-30, but the other day it did it cold. Well, the motor was cold, but the air outside was in the 80's, hot for here in San Francisco.
In this thread about an '83 240 you mentioned an easy test for a failed fuel pump check valve. Please share if this is applicable to the '93.
Thanks, as always, and again.
Chad

 

I failed check valve won't cause a no start but will require you to start the car repeatedly until it fires up making it difficult.

Your model year does have a crank position sensor
Which communicates with your obd1 box/ ecu.

As your crank the car gaze at your rpm gauge and look for slight movement of the needle.... If no movement than it is not communicating and will not give you spark! Hence bad crank sensor
Also run a onboard diagnostic and see what codes are stored up in ecu.

Goldenblock
L&D volvo Redblock parts
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Crank sensor is not a speed sensor... A speed sensor is housed on the rear differential cover and uses a magnetic pickup and relays that signal to gauge cluster to indicate mph. If that is bad it won't cause a no start, just an inaccurate or absent speed indicator on dash!!

One love
Goldenblock
L&D Volvo Redblock parts
Atlanta Craigslist
Shipping Nationwide

 

Thanks Goldenblock. Will run the checks. The symptom seems to be as you describe for failed check valve. It does not start for multiple tries then does start. Aggravating after alot of work done to service PCV, intake, injectors, new battery,plugs, wires, cap and rotor, fuel regulator, crank p;osition sensor (OEM Volvo).
Chad

 

And a new coil that was not needed after all. Due to the "no spark" condition we replaced the crank position sensor and seemingly restored reliable starting, at least for awhile. But I am now thinking it may be the fuel pump check valve since it requires multiple no-start crank attempts before it will fire up. Is that an intermittent fail? it sometimes starts first attempt. Other times it requires multiples. Thanks for your advice.

 

When you have a no-start condition, do you hear the fuel pumps run for a second or so when the key is turned to the II position? If not, your problem may be with your fuel pump relay. Check this link out for diagnosing fuel pump issues:

https://cleanflametrap.com/transferPump.htm

When the fuel pump relays start to fail they typically do so intermittently. What happens is that there is a little circuit board in the relay that develops cracks in the solder joints. If you are handy with a soldering iron you can re-flow the solder on the little circuit board and return normal function.

 

Hi again. Well, yesterday the car started right up in the garage. This morning it would not start. I pulled the fuel pump relay and checked for continuity. There is continuity between 2 of the 6 blades. I have not tested for relay operation with 12v yet. This relay is marked Made in Hungary, part no. 898151 and has date 13-11-2015 stamped on it.
Help is requested for the following:
1. all tests on relay;
2. fuel pump check valve test;
3. anything else that members have found for the mystery no-start condition on a 1993 240 wagon with auto transmission.
Further information about this car:
it has over 250,000 miles;
it has new emissions components (flame trap, etc.), fully cleaned and serviced intake manifold and nipples, new intake gasket, serviced and tested fuel injectors (new caps and washers and spray-tested), new fuel pressure regulator, new Volvo OEM crank position sensor, new distributor components (cap and rotor) coil, spark plugs and wires, new timing belt and tensioner and water pump;
a couple of months ago it passed California smog "like a new car" according to the test tech. The no-start problem started after all the service items above and the smog test but before the CPS was replaced, which seemed to solve the start issue. But the problem has worsened.
HELP. And THANKS

 

Based on opinions I have read here I am tending to think fuel pump relay and fuel pump check valve issues. Both are reported to give no-start symptoms intermittently.

 

I have read through the link about fuel pump tests and plan to try them. I will report results when i do. Thanks for that link. Very informative. But i think the simpler test first is fuel pump relay, next will be the voltage test at the pump fuse terminals. Your guidance is keeping me going. Thanks all.

 

The problems with testing relays is that they can be intermittent and test fine but then fail randomly. Next time it won't start, jump the fuses as described in the link I posted and then try starting. If it starts then most likely it is your relay. Like I posted earlier, the relays can be be repaired by re-flowing the solder joints.

 

Hi act1292. Thank you for the link. That is what I was preparing to do when I checked the fuses no. 4 and 6 on my 1993, and found the power fuse, no. 6, to be askew in the holder. When i went to correct it it fell apart in my hand! Put in a new red 16A fuse into no. 6 and it has fired right up since!
I learned my lesson. Always check first things first, the simple ones right in front of our eyes!
I was aware that no. 4 was the fuse for fuel pump relay but it was not until I read through the link you sent that I learned about no. 6 being the power fuse.
You saved me alot of frustration of trying to work on relays and fuel pumps.
Thanks again. I hope every DIY Shade Tree Mechanic like me reads your posts and follows the link.
Chad

 

I had saved the original relay dated 1992, Made in Germany, when I replaced it some years back when the tank fuel pump was the issue. I put it back in after i replaced the no. 6 fuse to see if it still worked but it did not. The replacement in there now is a 2015 unit made in Hungary. I am planning to use the bad original as my project to see if I can redo the solder points and revive it. As if I didn't have enough to do!