hi everyone!! I am new to this forum and fairly new to Volvo's. I recently purchased a 1987 245 automatic with 250,000 miles. I am going crazy because I cannot figure out why it is starting so rough when it is cold? I crank it it takes longer then it should to fire and the stumbles likes it is going to die then catches itself and idles up. Then I try and give it gas and it stumbles some more until I just wait 30 seconds or so.

I have replaced the computer temp sensor with new OEM, the O2 sensor new OEM, cleaned the idle valve motor and tested, replaced the bellows had holes in it), full tune(plugs,cap,rotor,wires,fuel filter,air filter,flame trap kit(All OEM)), it has a new timing belt, new in tank fuel pump(OEM), new main fuel pump(OEM), new thermostat(OEM), tried another computer(used), set my fuel/air mixture to spec(got the sweep), checked for vacuum leaks and set base idle. I have no idea what else it could be?? According to the Bentley I do not have a cold start injector cause it's an 88 with LH 2.2 not LH 2.4. Also all my fuel injectors are working...

Any ideas? Did I miss something? Fuel pressure regulator? carbon deposits? HELP PLEASE

Thanks All!!
Volvo240Rookie

 

some things to check:

- make sure the blade fuse by the coil and fuse 4 are clean.
- with the car off jumper the left sides of fuses 4 and 6 and listen to the pumps run. Sometimes the intank pump replacements are wired (and run) backwards.
- verify the throttle position switch is working.
- the fuel pressure regulator, as you suspected.

 

Thanks Bubba. So in tank pump is hooked up and working properly. The throttle switch clicks like it should but I was unable to get a good connection on it with my multimeter. I will clean my fuse terminal and check fuel pressure regulator. Started just fine this morning..so I guess it's an intermittent problem only when car and weather is cold...oh boy

 

Replaced fuel pressure regulator and reset mixture. Also put a can of Sea Foam in it. Tried to find BG44K but very hard to fnd retail. I will order a canb online. Friend says may be carbon build up on fuel injectors? Would a faulty knock sensor cause the car to run too lean? I will see how it starts tomorrow morning.

 

You know this sounds a lot like the problem I recently had with my '86 245. Mine is the manual transmission; I could keep the motor running by feathering the throttle, but when it got down to 2000 rpm it would die( or need a big shot of fuel from the accelerator). I did many of the things you listed as doing, also with no help. I finally called up a Volvo mechanic I was acquainted with and asked his opinion. He said "it's your air mass meter". I told him that I had checked it out with my multimeter and that it checked out OK according to the data in my Bently manual. He wasn't surprised at that; said they sometimes are in range, but the idle section doesn't work. ( I had cleaned it previously with no change). He was kind enough to offer to come by the house and put on a spare known good one that he keeps around for testing. He said "Bob, you are gonna be amazed when I put this one on and it fires right up"
Sure enough, thats exactly what happened. So I found a used one on a wrecked car for $50 and put it on and it runs fine.The one for the LH2.2 has an adjustable idle screw with a white cover on it; thats the one you need I believe. I suggest trying a used one; if it came from a wreck, you know that the car was running at the time of it's impact.

 

I have tried another MAF sensor and had same issue. From what I have read the screw adusts or feathers in fuel mixture turn one way and it's lean the other it's rich. It is a fine tune adjustment for the O2 sensor not an idle adjustment. The big black **** on the throttle body is how you set base idle. However, maybe I do have 2 bad MAF's?? Thanks for the advice and help.

 

The AMM screw is for the co2 adjustment ... its a variable resistor for the ECU

 

Anytime I had an idle problem with me 740 GLE, which had the same motor, it was a hole in the MAF duct that went from the MAF to the idle control valve. The other main idle stalling issue was with the idle valve sticking because it needed cleaned. I took it off the motor, cleaned it with carb cleaner, and put it back on.

As for the idle control valve, I doubt you can tinker with that. If what I mentioned doesn't help you, replace that thing.

 

Well I replaced the main ECU and trhe car is starting and running perfect. Thanks all for the help!!