Hello,
I had a new thermostat put in and now, when my 1995 850 Tubo is running, it is running at a good temperature. I still have that problem where when it is below 0* F, the car will start up, it will rev fine in park, but in drive or reverse it has NO power. It will get going to about 10 mph and up hills it can barely make it. If I let the car warm up for a while, it sometimes comes back to normal. When I rev it in park however, it is a little delayed. It doesn't bog or anything, it just has a little delay. I have no idea what the problem is. Any help is greatly needed. I did put dry gas in the other day and after warming it up it worked fine, but it could have just been a lucky thing.

***Alright, now I just had my o2 sensor changed because the mechanic said that the code he got while driving the car showed o2 sensor had problems. They changed that, around $250 with labor and now the car is still having problems. It will drive fine somwtimes, and once it even lost power while I was driving. I was going about 45mph and the speed just dropped to 20mph or so and it did that thing where it would not accelerate, and up hills it could barely make it. Now they say that is is a fuel related issue and that the car seems to be running "lean." Another thing that may come into play is that once in a while, my battery for some reason or another (maybe the below 0*F temps) will die completely. The digital time is not even present and the car wont even turn over. Could this all be an electrical problem that would hold back the fuel injectors? PLEASE HELP, its tough because I do not have enough money for people at the shop to keep "guessing" to solve my problems.

-Thanks

 

I am scratching my ever balding head trying to come up with any kind of causal relationship between replacing the thermostat and the problems you describe.

Does your temp gauge now read correctly (Pegged in the three o clock position)? If not theECTsensor wire could have been knocked off in the process of changing the thermostat.

The delay in the revs suggests a vacuum leak but I am not familiar enough with turbos to know what lines got to where and which lines are around the thermostat. The fuel pressure regulator comes to mind.

???

...Lee

 

I had the same problem. I barely had any gas in the car so I filled it up and it's run perfect since. I attributed it to moisture in the tank/lines. Now I always try and keep it above 1/4 tank when it's cold out.

 

Thanks for the advice. I'm very glad that you had found out your was freezing in the gas lines related. I say this because the mechanic I had seen had thought of this, and when I use dry gas, it seems to clear up. I don't mind that, I'll just try and keep my tank full instead of 5-8 gallons like I have now.

-Thanks

 

Hi Keith, when was the last time the car had a good tune-up? Sorry if I repeated this in another post of yours. Also, have you pulled any codes from the ECU?

If the fuel filter has not been replaced for God knows how long, it could have soaked up some water and crystallising in freezing temp, though it is not likely to cause the problem you're having but worth a look.


JPN

 

Another crazy thought is the transmission fluid. When was the last time it was changed? I once had a car with old/low trans fluid in it, and when it would drop below 0 it would do exactly as you described.

Anyway, just a thought

 

And another crazy suggestion is the fuel. When was the last time you replaced fuel? 99.9% of drivers never replace fuel and then....

......[8D].


JPN

 

I am expering the same thing you are. Let your car warm up before you drive. The oil is too cold when you start up and you need to let it warm up and build up that pressure.

 

The new issue is the 2nd paragraph in the original post. Thanks for any help!

 

Based on your amended description battery cables come to mind as a primary cause of your problem. This is particularly true if you have secondary cables that are bolted to the main cables (Some do and some don't). Remove and clean all of your battery connections - I assume your have your radio code since everything has died before.

This is one of the times of year - really hot or really cold - where fuel pump relays rear their ugly head. Try to jumper the relay and see how the car behaves. The fuel pump relay is relay number 103 and it is located beneath the shroud on you fuse box (The upper central electrical unit to be precise). There are 4 pins on that relay and molded into the plastic next to the pins are the numbers 31, 31b, 87, and 15. Run a jumper wire between the socket positions that correspond with 87 and 15. If the car runs OK you need to either rebuild or replace your fuel pump relay. Remove the jumper when the car is not in use.

It can be rebuilt for a couple of dollars if you know how to solder, I did a writeup here:

http://www.matthewsvolvosite.com/cha...pic.php?t=9681

Otherwise I think they cost around $50.00 to just replace them.

...Lee