Hello Folks!
I am having an issue with my 1991 Volvo 240 with 240,000 miles. It has a B230F engine. It has an LH 2.4 fuel injection system in the car. It is a solid car and would like to get it back on the road. I have an acceleration problem. When you open the throttle fast, the engine falls on its face. Open it slow, and it will rev. I have gone through the Bentley manual and checked everything that could be associated with the problem and I am at my wits end. I have been fixing the car up for several years and it was drivable till this summer. This is when the problem arose.
I did take the car to the Volvo dealership and they went through the car and they couldn’t find the problem. They first diagnosed a bad MAF sensor. That didn’t solve it. Then they replaced both computers and that didn’t solve it. Fuel pump relay was good. They finally gave up, put the old parts back on and didn’t charge me for their time and I thanked them profusely.
So, I started myself and found things that were out of tolerance or were really aged. I replaced them. This is what I have done to this point:
New plugs, wires, cap and rotor, O2 sensor, both temperature sensors, air box stat, TPS, checked the engine is times correctly, both fuel pumps and filter, vehicle speed sensor, IAC and flame trap hoses, cleaned the IAC valve and throttle and intake gasket . Engine has great compression and fuel pressure. I have checked the inputs to the computer and everything checks out.
Please HELP!!! Point me in a new direction so, I can get this car back on the road.

 

odds of a dealer still having a mechanic who even remmebers what a 240/740/940 looked like are slim to none. those guys are all indies now.

I think the first thing *I'd* be looking for is a bad air leak in the intake path.

 

Test the fuel pressure. May be a fuel pump issue. Blipping the throttle quickly should get you 42psi, if not, what you describe happens.

 

Possible the intake hose has rubbed a hole on the bottom against the wheel well.

 

I was told that the guy who worked on it was there when the cars came in new. The air leak would be after the MAF sensor? That would be the only place since the intake gasket was changed, correct? Thanks for the reply.

 

Forgot to mention that the fuel pressure regulator was changed when it sprung a leak a year ago. Dealer check the pressure during their diagnosis and I was told it had plenty of fuel pressure. To verify this, what would I use and where would I hook in? Thanks for the reply.

 

Thanks for the reply, will do.