S80 2000 2.9 non-turbo. This car developed a starting issue a few years ago. I changed almost every sensor, re-routed wiring, cleaned and had throttle body re-programed, Immoblizer, keys, Good grounds. fuel pump, o2 sensor, battery,still a starting issue, runs great after starting. Will start great sometimes, and the next minute, just won't kick over. Turn off ign. for a few seconds, and then it fires right up. I don't have the usual throttle body symptoms, just the starting issue. Could bad electronics in the throttle body cause this starting issue? I want to send it to Vex to upgrade, but I'm afraid I'll still have the starting issue when I get it back. any opionions?

 

Does the tachometer jump when it will not start?

 

Not any more, I re-routed the crank sensor wire away from the starter cable, etc. That was the first thing I did when this issue started happening. by the way, Volvo dealer had this car for a month, and could not find the problem except for the ground wire going to the tranny was loose. They fixed that. Gave the car back to me and said they don't want to see it again. It's still the same. This is the second throttle body on the car. That was done before I bought it. One other thing that I noticed, when I turn the car off, the throttle body makes a strange noise for about 10 seconds afterwards, kind of like one of those air pumps used to inflate tires. It's deffinetly the throttle body making that sound. If you touch it you can feel it also, it's kind of like it's trying to re-set something, I don't know if that is normal, or what it's trying to do.

 

Did that, let me add that when the car is cold, it's 18 degrees out there now, she kicks right over, after the engine compartment warms up, starts with the problem.

 

I wonder if it is a thermostat or ECT sensor issue?

 

Has the fuel pump been looked at to make sure the nipple is not cracked?

 

Have you changed the coolant temp sensor?

 

Coolant Temp Sensor

Is this sensor different from the reading on the dashboard? I'm guessing this wouldn't throw an error code as well?

 

It will not always throw an error message.

 

My issue has to do with the car stalling when it is cold. After it is warmed up, the car runs fine. Do you think that this coolant temp sensor is at fault? I've read where one fellow thinks that a cracked J-hose is causing a vacuum leak. This is beginning to sound more logical.
There are times when the engine operated 100% fine. For those you have replaced the J-hose, what were your symptoms other than a CEL . I'd rather replace this hose than spend $50.00 for a sensor that might not be the issue.

 

I have not changed the coolant temp sensor yet. Seems like it is really hard to get to., a project for spring. Volvo dealership said they tested it, and the readings were correct, but I really don't trust them. They have no idea what they are doing on an S80. One dealer said I need a new engine because a few cylinders were a little lower PSI than the others, I believe it was about 10 or so PSI difference.

 

I bought the Throttle Body but my mechanic cannot find the part on my car. Does anyone have a diagram or can they tell me where to find it.

Thanks

DL

 

It is under the intake manifold.