1988 Volvo 740 Turbo wagon, time to put her down?

Hi all,

I apologize in advance for the long post, but I?m trying to figure out if the number of problems I?ve had lately are related.



My 88 Volvo 740 Turbo wagon (244k miles ? that?s enough to get to the moon!) has been a good car. I’m the third owner and have had it for about five years now. It’s had more problems than usual lately, and I’m trying to figure out if the scales are tipping and I should get rid of it. I’m not a car guy myself and, don’t have a mechanic-friend from whom I can always count on a straight answer. The word I get is that even very trustworthy mechanics often misdiagnose volvo problems unless they specialize in swedenwagons.



FWIW, this has been a second car, mainly driven only around town. One year we only put 12 miles on it. Now, due to a new job, the second car has become a little more critical than it was.



So here are the problems:

Since I got the car, it’s done the following at startup. The engine starts - almost always on the first try - and revs up, then down, and up, and down. It used to go between about 1000 and 2000 RPM, if I remember correctly (I?ll explain my uncertainty and the ?used to? soon). It does this for a couple of minutes. Seems like until the engine is warmed up. If I try to drive before this is done, it will likely stall at a stoplight. If I wait, sometimes it would dip low enough to turn off, but would start back up.



In May, the timing belt broke. This is one of two times we?ve driven it more than 100 miles. Fortunately, this is not as big a problem on this car as others (I?m told) and nothing was ruined, but it was about a $500 repair.



It ran much more smoothly after that. I?m told that?s to be expected. The up and down idling at startup persisted, but now goes between about 500 and 1500 RPM, and will always stall during this warm up period if I don?t give it a little gas as it heads toward 500.



One hot day in June, I stopped to wait for a train crossing. After a little while, I put the car in park and turned the motor off (the train had started backing up, then going forward repeatedly ? no end in sight). When the train finally cleared the road, the car wouldn?t start. I tried several times ? even tried giving it a little gas, which I?ve been told not to do (and the manual confirms not to), and it?s true - it never helps. So, I decided to wait for about two minutes. Tried again and it started fine. Proceeded to the grocery store. Shopped. Got back in the car ? wouldn?t start. Waited again ? started fine. Always started fine after that (until yesterday?)



Next incident was two weeks ago, when, due to faulty planning, I ended up driving the car from Northeast PA to Atlantic City. Passing through Philadelphia, I pulled the car over to the shoulder (on I-95). I did this pretty fast, because I wasn?t sure if the next exit was the right one, and there was no one behind me, so it seemed safe. Checked my directions, no prob. Pulled back onto the road, no problem. About a mile later, the engine seemed to lose power. I?m not sure how reliable my memory of those tense seconds is, but I think that pressing the gas had no effect. I eased it back to the shoulder, and by the time I rolled to a stop, the engine was off. Wouldn?t start again. I tried several times, waiting several minutes between each time. No go. Called AAA. Waited. I don?t know why, but after about 30 minutes, I tried again. Started up. I had about enough time to get a AAA rep back on the phone before it turned off again. I waited for the tow. The garage replaced the ?ignition power control unit?. He said it looked like it was an original part, and that they do just wear out. I mentioned the train tracks incident, and he said there was no way he could tell if the same component was to blame, but that he was sure it was the problem this time and that I was good to go. Again, about $500 (also repaired a trans fluid leak), I drove the car 2 hrs home with no problem.



Fwiw, I?ve replaced the battery 3 times during my ownership. Battery #1 came with the car, and the mechanic just said it was old and dead, and it seemed to be. Months later, the car wouldn?t start and I took Battery #2 back to the mechanic, he confirmed Battery #2 was permanently dead and seemed genuinely surprised. It was under warranty, and he replaced it for free. He mentioned that I should be sure to start the car at least once a week when the weather is very cold, and that other than the battery being defective, that was the only thing he could think of to explain the premature death of Battery #2. After going through the next winter, Battery #3 was dead, and I have to say I?m sure I went more than a week between starts during some very cold weather. So I paid for Battery #4. That?s what I have now.



Yesterday, I went out to start the car (again going to the grocery store ? maybe I should just avoid grocery trips in this car) and it wouldn?t start. It actually seemed to be turning strongly, but wouldn?t run. I waited several minutes (my only technique, can you tell?) between a few more tries before getting a jump from a neighbor. It started right up.



And this is where it comes back to my original pondering as to whether these problems are related, which might make future repairs a bit more predictable. The car runs so well when it runs that it keeps my hopes up.

I?m also open to suggestions on a good course of action from this point? I?ve finally found a recommendation from a local mechanic who specializes in European cars. I could take it to them and ask them to see if they can determine the reason it didn?t start?



I know a car this old is bound to have problems. It needs an oil top up every once in a while, and odds and ends fail (antennae stopped working, as did the sunroof ? hated to lose that sunroof), which I see as unfortunate but normal and not worth fixing.

But how to decide if it?s best just to get rid of it altogether? If it?s going to start needing $500 worth of work every few months, it makes no sense to keep it.

One reason I?m slow to pull the trigger is that I can?t afford a new car outright (not a fan of making payments) at the moment, and know so little about cars (and have ended up with two lemons buying used) that I?m very reluctant to buy a used one.

Okay, that?s more than enough. Sorry again for the lengthy post. Any advice much appreciated!

Best,

Nathan



The LH Jetronics system on this car uses a thin wire Mass AirFlow meter so it should be checked for correct operation and given a cleaning. Also check the plumbing from the MAF sensor to the turbo compressor inlet and from the compressor outlet to the throttle body to make sure there are no leaks or breaks. Also just for good measure make sure that the compressor shaft air seal is not leaking.

Also this system still used a start injector. I don’t remember the exact parameters for when it is turned on. As I remember there is a coolant temperature switch that keeps it from coming on when the engine is already warm. So I would have the mechanic make sure the start injector is coming on when it is appropriate.

You might have your mechanic give you a few tips on leaning or enriching the mixture to narrow down why the engine is not starting and how to check for spark. You have to find out if it won’t start because the mixture is too lean to burn; too rich to burn; or there is no spark at the time it won’t start.

Hope that helps.

Since I first posted, I’ve been reading lots on the various online forums and have found that, as you suggested, the Mass AirFlow meter is a frequent troublemaker for volvos like mine. Also, there are a couple of relays that are often to blame. I am getting spark - I’ve learned how to check that. It seems the relays are often responsible for a lack of fuel.

I’ll follow up on these with the mechanic. Thanks for the help.

Also, the persistent revving up and down is typical of a vacuum leak. The fact that it only happens when cold tells me it is on a vacuum circuit that is connected to a thermo vacuum switch. These switches are typically located in the intake and near the thermostat housing. They use the coolant temperature to activate and de-activate specific vacuum circuits. Since the problem goes away once warm, check these lines first.

Thanks BK, I will do that. Based on other reading, the idle air control valve on these volvos is very suspect, too, when it comes to cold idle issues and needs to be cleaned. There’s definitely a journey through all the vacuum lines in my future.