Chapter 6,329 of the ongoing "Saga of The Lugging '89 240 DL" or "The Same Problem, Different Cause and $2000 Later."

Here's a short re-cap of the problem:

Engine starts lugging at 1800-2200 RPM under load. The ultimate problem (the first go-around) was that the indexing of the distributor shaft was off from the rest of the mechanism (crankshaft and cam position) which caused spark to be lost in cylinders 2,3 & 4 above 1800 RPM.

The problem was solved after fixing the indexing of the distributor shaft (it was somehow off by one tooth on the gearing); new mass air sensor, coil, wires, plugs, crankshaft position sensor, fuel filter, throttle position sensor, new injectors, and new several dozen other components that the mechanics bumbled through in their tube-pulling effort to finally fix the problem, they claimed to have checked the fuel lines for any leaks, claimed to have checked fuel pressures for the low pressure and high pressure fuel pumps, etc.,,, (I had to tell them several times what the problem was before they checked the distributor timing before they finally said, "duuuuuuh. Why didn't we think of that? duuuuuuuh).

So, after three months of the mechanics putzing around, we finally got the car back and it worked fine - for two weeks and now we have the very same problem again.

The difference this time is that there is no loss of spark, but all the symptoms are exactly the same. If you are at 1800 - 2000 rpm on the flat, there is no lugging, that is, until you try to accelerate past that rpm range under load. Then the engine lugs and you are picking your teeth out of the steering wheel and dashboard. But the second you give it a little gas at that engine speed, it's lugfest on steroids.

If you rev the engine in neutral, there is no lugging in any rpm range and no loss of spark.

I checked the compression and it is right in factory specs.

Now - would I be correct in assuming that this is a fuel deliver problem and that the mechanics didn't really check the fuel pressure, etc? Or am I just a totally untrusting person who thinks that some mechanics are incompetent ***** who want to pay money for their incompetence?

 

just out of curiosity did anyone check the fuel pressure regulator?

 

The fuel pressure regulator is OK. Or, at least they claimed it was OK.

The odd thing is that after they properly indexed the distributor (which was set one tooth off for some odd reason) and "Fixed" all the other issues, everything was fine for about two weeks and then the problem came back.

Here's an additional test I performed today. I took the car down the Saluda Grade (a 7 mile long 7% grade on I-26 in North Carolina. I allowed gravity to take me past 2200 RPM and got the car up to 70 MPH on the flat coming out of the grade. Above 2200 RPM, you can accelerate to your hearts content as long as the RPMs are above 2200 RPM. At 2300 RPM and above, you can dump the throttle and there is no problem at all.

Essentially, if the engine is under load (meaning you have to give it throttle between 1800 and 2200 RPM, it will bog. If you are above 2200, you can punch the accelerator and there is no problem. It is just in the 1800-2200 RPM range you get the bogging and stumbling (no loss of spark).

Is it possible that the fuel filter got a dose of dirty fuel from the gas station?

The problem seems like something is disrupting the fuel delivery but only in that RPM range while asking to accelerate in that RPM range in any gear.

Here's another funny part - the problem started out (in both pre-repair and post repair) only in 2nd gear. The started to happen in 3rd gear. Then started in 1st gear and then finally 4th and then 5th gear in that order and then went downhill from their as the bottom threshold of RPMs where the problem occurred got even lower. Now the failure is between 1200 RPM and 2200 RPM.

I've had four mechanics "fix" this problem (including two Volvo Dealerships) and the problem keeps coming back after two weeks or so. Each time it costs me about $2000 and they replace all manner of parts and two weeks later, the same problem, but with "different" causes. I think I'm just being taken for a ride at this point.

My next solution is to just junk the car and be done with it because every "repair" last two weeks and then the next mechanic wants another $2k out of me for a fix that fails automatically in two weeks, every time, without fail or exception.

 

Here's a video that might help you out, part of the test will have the "ECU" do some test, like on some new cars they call "Mode 6" where the ECU test the transmission solenoids, ABS pump, ect. I watched it twice to get to sink in, good video though!

Tell us what turns up!

 

No error codes. Input and output for the ECU is as it should be.

What's the possibility that it's just a bad load of fuel?

 

It could very well be bad gas but you probably have gassed up a couple times in two weeks.
I leaning towards a plugged CAT. On some cars I've worked on I pulled the O2 sensor out and tied it out of the way, it was just enough opening to let the engine breath better and ran better than before.

 

I thought about it being a plugged catalytic converter but, if the problem stopped for two weeks after they worked on the car, that would indicate that the CAT suddenly became unplugged and then plugged up again. This makes me lean towards bad fuel (which is more common than not in my neck of the woods). All it takes is one bad load of fuel and a few miles down the road you have a problem. The only difference was that we put regular gas in the tank because every stinking gas station was out of super grade. But that shouldn't cause this type of problem.

The other possibility is a leak in the exhaust system past the catalytic converter causing excessively low back pressure causing the CAT to heat up more that usual, thus throwing off the reliability of the signal from the O2 sensor. Possible, but not likely.

Another SWAG (Scientific Wild *** Guess) could be a plugged fire trap.

Also, the fuse for the backup lights/rear wiper keeps blowing. The problem gets worse with that particular fuse blown. Go figure. Someone said that if that particular fuse unrelated to the in-tank fuel pump blows, it is generally that pump sucking too much current causing that particular fuse on an unrelated circuit to blow (a Volvo Mechanic floated that possibility).

I had a Volvo mechanic who works at a dealership give the car a once-over and he said he hasn't a clue what would cause this. There are no error codes (unless some error codes are buried in that jackass diagnostic system design and said codes do not trip the check engine light) and all the various components check out OK.

The first time this happened, the cause was determined and fixed at great expense. Now, we have the same exact problem again, but cause by a new and unknown problem.

But I will try pulling the O2 sensor and see if there is an improvement.

 

Pulled the O2 sensor and the problem persists.

Took the car to a Volvo dealer and they said junk it because this problem is one that Volvo has never been able to solve.

 

Well, seems a shame to junk it after you been through but if your having wiring issues too it might be the thing to do and call a learning experience.

 

The problem is, that I have had this problem going on about seven time. Every time, the mechanics have to fix exactly the same things over and over again. And every time the same problem comes back after about two weeks. And these aren't cheap parts. MAF meters, etc.,,,. Every time, the timing is mysteriously out because the "distributor slipped a gear", etc.,,,. It's the same problem every time at $1500-$2000 a pop. And the problem keeps coming back. No one can solve it, Volvo dealerships cannot solve it, and after thousands and thousands of dollars, I end up with an undriveable car.

I've had the entire car rewired down to the cigarette lighter and the problem persists. New Jetronic units and every other component related to it. Still the problem comes back after two weeks and I'm back to the beginning. This goes to show that not even Volvo is capable of working on their own vehicles. I've talked to Volvo engineers and Bosch engineers and they say this is what eventually puts every Volvo in the crusher - problems that not even the engineers can suss out.

I pulled the O2 sensor and even pulled the Catalytic Converter and still the same problem. Replaced every stinking wire and electrical component, replaced every vacuum line, checked the fuel pumps, the fuel lines, the fuel pressure regulator, you name it. I think we've got about $15,000 into this car in repairs in less than three years and still we get the same result: after a repair, we get two weeks and it's back to the shop with the same problem.

It's junk yard time for this car because I am fed up with mechanics who don't know enough about their own vehicles to fix them.

 

just because they 'said' it was good doesn't mean that it is good.
the test is simple pull off the vacuum line if there is gas present then it is
bad....

 

why would you take a car this old to the dealer? they don't want to know and probably will say anything to make you go away. it's not worth it for them to screw around with 89 240's in their service dept.
if you don't have an independent mechanic that is fully familiar (and old enough) with these cars or work on it yourself then this is not the car for you. it does not make sense to put 2k into a car worth 1500..
you would be better off with a corolla or civic being boring but reliable machines...
good luck.