87-240 Hestiation at acceleration

Harry von Zell · Post by **Harry von Zell** » 29 Sep 2007, 15:35

Well folks, my 87 has been "choking-out" when I accelerate from a dead stop. Car just dies when I hit the gas and it also will "choke-out" when I accelerate heavily at 30-50 mph.

Smart guy that I am (not), having had 2 other bricks, I was convinced it was the dreaded air-mass meter, so I took the bite and replaced it.

New meter, same "choking" problem. Aaarrgghhh!

Any Ideas?

TIA, Harry

wojeepster · Post by **wojeepster** » 02 Oct 2007, 18:23

look at the accordian hose from the air mass sensor to the throttle body. If the fender has rubbed a hole it allows unmetered air in. Run techron or your favorite brand through the injectors (injector cleaner) If one injector is off the o2 sensor can change them all adjusting for that one. See if throttle body needs cleaning. Look at plugs, if black check fuel pressure regulator, if pressure is high car goes very rich......

Harry von Zell · Post by **Harry von Zell** » 03 Oct 2007, 08:29

Thanks, my next door neighbor is my city's chief municipal mechanic and has a complete shop (with a full lift) in his "oversized" garage.

I'll pass your comments to him. Car has run rich for a year with a very high NOX reading. I'm guessing it's all related....

wojeepster · Post by **wojeepster** » 03 Oct 2007, 15:30

If it has been running rich I vote for fuel pressure regulator

Harry von Zell · Post by **Harry von Zell** » 04 Oct 2007, 08:50

Replaced it 6 months ago. Nothing changed, still high NOX. H

wojeepster · Post by **wojeepster** » 04 Oct 2007, 12:14

is it possible that you have a leak in your exhaust manifold that is allowing 02 into eshaust? O2 sensor just measures o2 it doesn't care where it is coming from, if you have this it would throw the rest of the fuel injection off, as would hole in accordian, vacuum leak, deterierored orings around fuel injectors...... with orings on fuel injectors you would have crappy idle, especially upon startup that would get better as car warms up.

A.Baker · Post by **A.Baker** » 14 Oct 2007, 21:01

Because your freind has access to all the goodies. Have him conect it to an ignition anilizer and look @ the raster rise and fall. You can find a failed ignition componant real fast, I.E. Plugs,wires,cap,coil and the like. At least you will be able to take that out of the equation. Than The gas analiser.
Good luck.
A.Baker

Harry von Zell · Post by **Harry von Zell** » 16 Oct 2007, 08:14

Car is now in full "limp" mode. Limp kicks in when engine warms up. I printed all your comments, to give my "neighbor/mechanic" a game plan.

He has already replaced the AMM, with no results.

Any other "ideas" welcome as he is not a Volvo specialist.

Thx, Harry

tripleb · Post by **tripleb** » 17 Oct 2007, 20:08

Just to add to the great posts already...

A plugged exhaust (catalytic converter)

coolant temperature sensor

engine wiring harness deterioration

B