Hey y'all
I've got a 1990 volvo 740 wagon with the 4 cylinder gas engine that fires right up and idles fine but......if I start driving it it stalls out and won't start back up. My thought is the fuel injectors are sticking open and flooding the engine. What are y'all's thoughts?

 

Any codes on the OBD? Could be one of several things, the injectors far down the list. Could be the FI relay, the Crank Position Sensor, the Coolant Temp Sensor, the MAFS (mass airflow sensor), etc. Need more testing.

 

Easy way to check for fuel flooding is pull a spark plug . If it's wet then it's an injector issue. If dry then it's fuel pressure or some of the other issues listed below.

 

Have you checked your fuel pump and noise suppression relays? Engine speed sensor? Checked for spark? What does it look like inside the distributor cap? Checked for injector pulse with a $5 noid light? "Sticking" fuel injectors would not be a choice - that does not happen unless there is a permanent control unit malfunction.

 

Ok, so after figuring out how to use the obd deal on this car I got code 2-2-1 and also code 1-3-2 with the selector in port 2.
Also sure if this is a related problem or not but the car seems to run fine in park and neutral but when put in gear it start to run ROUGH and bogs down badly

 

Ok y'all, thanx for the replies so far, I'm just going to keep adding bits of info as I test/research different things, I just bought the car last week so I'm still learning about it. My car has the B230F engine, and it is giving me the fault code 1-3-2 and 2-2-1 when I have the selector plugged into port 2 on the OBD.

 

221 is a lean code - Low fuel pressure, air leaks, bad air mass meter are possible causes.
What's your fuel pressure?

 

try this

https://www.troublecodes.net/volvo/

 

thanks 👍

 

Update:
I changed the oil last night because who knows when the last time it was changed was. And the oil was the consistency of gas and smelled and felt like straight gas. Next I'm going to change on the fuel filter, see if that does anything, and while that's off I'll check the fuel pumps and pressure.
The link that silvermine posted said the 1-3-2 code is saying there's something up with battery voltage, and the 2-2-1 code says there's something up with the "heated oxygen sensor, (rich mixture/part throttle)" would that influence the stalling and rough running while in gear?

 

221 is the o2 sensor reporting a lean condition so it will enrichen the mixture. Don't replace your o2 sensor as a first step - it's probably still ok. You may try driving with it disconnected to see how the car runs (the fuel map in the control unit will let the car run normally as long as the signals from all the pertinent other sensors are working correctly.) the O2 sensor can only change the fuel mixture very slightly - Low fuel pressure/air leaks can cause a lean condition.

For your "oil smells like gas" - some of those bosch fuel pressure regulators will stick closed, only when first started cold in the morning - the only way to catch it malfunctioning is to have your fuel pressure gauge on overnight. That floods the engine, and it's a rare occurrence . The regina fuel pressure regulator never had that problem.

The bosch fuel pressure regulators also break the diaphragm inside also - causing fuel to leak out of the vacuum line - that will dilute the oil also.


Courtesy of

https://www.volvoclub.org.uk/faq/Eng...agnosticCodesi


2-2-1* Fuel trim (lambda control) too lean at part load Lean; air leak; low fuel pressure; bad AMM Engine stops when starting from cold; high fuel use

 

It's most likely the MAFS, those codes on the OBD often pop up when the MAFS is bad even though they stand for other causes. First make sure no air leaks are present.

 

Update
Ok, it's still running rough, backfiring and lacking any sort of power. So far I've cleaned the MAFS, replaced the air filter, checked the fuel pressure regulator (it's not leaking fuel into the vacuum line), ran berrymans and a fuel injector cleaner though it, with no Improvement. I pulled the spark plugs and 1, 2, and 3 were pretty fouled up with carbon, and 4 was wet with gas. Anybody know what that could be telling me?
I also did an experiment with the fuel injectors. While the car was running I unplugged then plugged back in, the injectors one at a time to see if it changed how the car sounded. Unplugging injectors 1 or 4 didn't change anything, but unplugging injectors 2 or 3 killed the engine. Are injectors 1 and 4 bad and in need of replacement?

 

Cleaning MAFS rarely works. The test you did with the injectors does show 1 and 4 possibly bad, but do a pattern test to make sure, they are pricey. Also change the plugs, put some copper NGKs, gap them first...

 

You just found out it's not firing on cyl 1 and 4 at idle. That was not a test of just the injectors. Compression, spark and fuel - all three have to be working for a cylinder to fire.

So it's idling on 2 cylinders - could be many reasons for that - If the car is still driveable it must start running on 4 cylinders above idle (a 2 cylinder Volvo won't be driveable)

If you think 1 and 4 injectors are bad - move them #2 and 3. Repeat your test.

 

By pattern test do you mean spray pattern? And this is probably opening up a whole nother can of worms but, why copper NGKs? Thanks for the reply 😎

 

I'll try that tonight when I get off work. Then change on the spark-a-la-tors 👌

 

Use what the car came with - copper spark plugs, not platinum plugs, or iridium, or unobtanium, or splitfire, or double or triple fork. I used bosch (wr7dc+?) but ngk are a good brand also.

 

NGK coppers are cheap, less than $2 ea. and last 15-20k miles, not long, but the Red blocks seem to like them. Toward the, 1995, Volvo was recommending the NGK as OEM.
Also, good point, you don't have two cylinders' injectors totally out as the car would not run but you may likely have two injectors over or underperforming so the car runs but badly.

 

OK, I picked up a set of NGKs, see if that helps. I may try taking the injectors 1 and 4 off, cleaning them, and sticking them back in because I just checked how much a set of new ones would be and almost pooped my pants 😜. 80 BUCKS A POP! Have any of y'all tried rebuilding injectors with success? Like replacing gaskets and such?