Hi

Haven't been on here in a while as my 2 volvo 740's have been running great.... Well, until now that is.

I was driving my 91 740T wagon home from work today, when it died and I had to pull off on the side of the highway.

I let is sit for a bit and checked my oil (It was fine). I then checked my gas cap as I just filled up (It was on). I tried to start it again, and it would turn but wouldn't start. All my lights, blinkers, and electronics work. I left the key in the on position and waited a little more. After about 30 min, I stepped on the gas peddle and tried again. It barely started/revved then immediately died. I had to wait for 2 more hours for a tow truck, who drove me and my car back home.

The engine is not seized, the battery is good, the timing belt didn't break. I'm thinking its either a clogged fuel filter or bad fuel pump. Before I go replacing things, could someone please give me some more troubleshooting options to pinpoint the problem? I have a spare fuel relay that I'm going to pop in tomorrow, just to eliminate that possibility.

Thanks everyone! All and any comments would be greatly appreciated.

At least I still have my 89 740 to get me around till I fix this

 

I'd start with this troubleshooting guide
Engine Tune and Performance

 

I'd start with the usual issues. Fuel and spark.

 

Thank you for the prompt replies!

I will be troubleshooting this out over the next few days and will update this thread as to my progress.

Any additional comments or tips are always appreciated

 

yeah, what jagtoes said. first thing to do is figure out ofi ts spark or fuel. one easy test is to try starting it, then quickly pull a spark plug and see if its wet and/or smells of gasoline. or even just sniff the tailpipe right after a couple 5 second cranks, and see if you smell gas. if you smell gas (or the plug is wet), then its probably a spark problem. if you don't, then its probably a fuel problem.

cuts the potential problem space in half.

I'd really like to discourage blind parts buying because so-n-so's brother-in-law said its always ____.... much much better to diagnose the actual cause and just replace whats broken instead of throwing lots of money at it and hoping something sticks.

 

Hi

Well, there has been an interesting turn of events. Yesterday after work I started to troubleshoot out my car problems.

I turned the key to on, and listened for the inline pump (It pumped), I then put my ear to the gas tank and had my girlfriend turn the car over (The tank pump worked too). And much to my surprise the car started right up!

I drove it around for a little bit, and besides a little smoke out the exhaust, everything seems OK. The engine light was still on from the day before, so I checked the codes. I pulled a 2-3-2 code, which I guess means lean/rich fuel mixture or O2 sensor.

Seeing how I (now) have spark and fuel, any suggestions based on the above discription and code? I did just buy 2 fuel filters, as I haven't changed them yet on either of my volvo's.

I agree pierce. I don't want to strart buying things until I know what is wrong. Thanks for the comments and for helping me solve this problem

 

Intermittent fuel problems are often caused by a bum relay. This can usually be fixed by resoldering the terminals in the relay.
Ed

 

Maybe the air flow meter? I've had two Bosch's go in the past, with most of the same symptoms. $30 for a 2nd hand replacement.

 

Hi

My problem is solved and just wanted to update this thread to help others. I appreciate all the help I received!

So after checking for spark, I realized I had a spark, not fuel issue. Since I have 2 volvo 740's I just kept switching parts to trouble shoot out what was wrong!

I swapped ignition coils, power stages, and suppression sensors (One at a time). All of these did not start the 91, and would still start the 89. That left the RPM sensor and maybe the ECU.

I ended up taking it to an independent volvo shop to be sure, and they told me it was the RPM sensor. I ordered it from FCP for $35 and was charged 60 bucks to install it. They also changed my fuel filter, and I paid to have them do the timing belt and front oil seals (All parts I had previously bought, they did not order anything). All of this cost an additional 200 bucks. My 740 was leaking oil out the seals, so I was going to get around to doing it eventualy. The funny thing is, they told me that the crankshaft seal was completly missing (not just popped off, it literally was not there). I wasn't leaking oil that bad but that's crazy!

For me it was money well spent! It's miserably hot, I have to many other things going on. I'm glad I took it to the shop! Also, I now have a trustworthy, relatively cheap mechanic to work on my Volvo's


Thanks!