850 turbo 1996 runs way to rich when cold

[jblackburn]

it used a quarter of a tank of gas to go five miles

Holy CRAP! You're putting Hummer drivers to shame there. I don't know how the engine could even run with that much gas. You're not getting any engine codes at all?

The idle air control valve in combination with the ECT and the computer help regulate the idle at a cold start. Both of which you've replaced.

I wonder what kind of signal the computer is sending to the injectors though? Could it be a bad ECU?

Maybe you could pull the injectors and see if they are actually pulsing or just stuck open.

[marginal]

Hi alexpia.

Which thermostat did you put?
This one is for colder temperatures.

After I installed it, the temperature gets a little higher.

[alexpia]

i used a 192 degree thermostat. thats what was in it. every once in awhile when it is warmed up i will get front o2 sensor input voltage too low but not all the time. i did a fuel pressure test on tuesday had around 40lbs i didnt jump the relay terminals to test fuel pressure i did it with a guage on the schrader valve while the car idled. i was hoping it was a bad regulator but doesnt seem so. i took the ecu out of my other 96 turbo wagon the car ran no different. like i said if it is above 30 degrees it seems to run good but not as good as my wagon when its warmed up it runs better but you can still feel that the car doesnt seem to not be firing right. im getting to the point with this car where i may just take some parts off of it i need for my wagon and then scrap it. but it looks pretty good and the suspension is tight so i would rather fix it. im very curious to figure it out now but sometimes it discouraging. it shouldnt be this complicated to fix this thing. when i bought it the cel light was on for the front o2 sensor the back one was replaced in 07.also the tcv was bas bas causing it to overboost and shut the injectors down at high speeds but thats been replaced since. i often thought that may have something to do with it also. but not sure. i did notice that on my scanner the tps reading is different on this car than my wagon i believe the reading on my wagon is 9. something and this car is either 11.something or 13 i cant remember.maybe the throttle body is bad? i see alot of them for sale on ebay.

[Pauloil]

what did you replace the iac with: new or used? IF used it could be dirty.

the air intake thermostat could be bad, look at:

https://www.matthewsvolvosite.com/forums ... sc&start=0

you could check to be sure the current ect has some resistance: I once put in a new ect that was bad from the start

[alexpia]

i replaced it with a used one that i cleaned with degreaser it was moving freely when i put it in i also tried the one from my wagon that runs normal. there is an air intake temp sensor on a turbo? if so where cuz my haynes manual says its only on non turbos. i will look for it. this whole problem is probably something stupid or obvious. maybe ill have to only use this car as a summer ride lol and buy another turbo wagon. i wonder if a bad intake manifold gasket or bad injector seals? idle is 840rpms.

[alexpia]

yeah i used an aftermarket one from fcp groton and it was bad from the minute i put it in so i got an original volvo one and put that in. the symptoms from the bad one were my temp guage acting somewhat like a tachometer and the engine surged than stopped. after i changed it to the volvo part it acted normal no more surging or funny guage. ill run an ohm test on this one and brave the 20 degree cold and look to see if i have an airbox thermostat.

[alexpia]

i checked to see if i have an airbox thermostat or temp sensor nothing in there. my cruise control doesnt work maybe that could have something to do with it? im thinking of trying a used throttle body i know 850s had a recall and problems with this.

[jblackburn]

i checked to see if i have an airbox thermostat or temp sensor nothing in there.

There isn't one in the turbo models.

my cruise control doesnt work maybe that could have something to do with it?

Most likely a vacuum leak, switch, or something unrelated. The vacuum line into the pump under the battery is prone to cracking on many cars, and the cruise control ceases to function.

I suppose the throttle body (or the gasket) could be letting in unmetered air. Have you checked all other hoses for leaks and cracks? I left the clamp undone on my intercooler pipe once, and as soon as I got on the turbo it blew the hose off and ran horribly the rest of the way home. I didn't get a CEL either, which I thought strange.

[alexpia]

Yeah I checked all the turbo hoses and every vacuum hose I can get and all the elbows. I had to change them all in my wagon. As I said before the car runs the worst the colder it it gets ouside I started it up at 30 degrees the other day and it ran alot better than when it was 17 out and once it warms up it gets better but it still doesn't idle smooth but alot better than when it's cold. I'm not getting any black smoke and when I drive it and get on the throttle I don't get any smoke. I've either replaced everything electrical or fuel related it leads me to believe that there may be an air restiction but I can pin point where the exhaust tip is black but so is the one on my wagon. I can get a throttle body on eBay for around 50 bucks so I'll give it a shot at this point what's another 50. Does it matter if my car has no egr can I use one from a car that has an egr. I know I should use one from an automatic as mine is. If the throttle body doesn't solve this I'll have to break down and send it to the shop. Cuz I gotta know what's now. Even if I dont keep the car.

[bobsnow100]

Have you ever checked you fuel injectors? They could be real dirty and not closing.