Hello,
Wondering if someone will chime in with a problem on my 91 intercooled 12 valve, 5 speed.

There is a flat spot with acceleration, most noticeable in accelerating in 2nd, then 3rd, still felt somewhat in 4th and a tad less in 5th. I rarely use 1st gear.

The flat spot is there in neutral also, when I manually accelerate the engine at the throttle linkage.

It`s not a bad flat spot, but it still causes the truck to jerk when driving as the engine works through the power loss momentarily. Flat spot is consistently in the same rpm, and is always there.

271 000 kms, everything stock. No engine or pump, or injector repair or mods done since I`ve owned it, from the 100 000 kms mark on.


Also, there seems to be a horrible screetching sound coming from somewhere in the front of the engine. Hard to explain the noise, but it`s best described as a screech, cyclical, grind. It works up to a cresendo, starting softly, then increasing in volume and intensity with acceleration until it`s pretty much a scream type howl.
Others on the road will turn and look at my truck when they hear it, so it`s pretty loud.

It may last for the first 2kms of driving, then goes away. Seems to happen with a cold start up, and not a warm start.

When it happens, and I depress clutch and coast, the noise lessens and almost goes away.......but starts right back up when I release clutch and continue to drive. It`s worse with acceleration and less with light load and coasting.

Had the truck to the local repair shop ......they thought it was the serpentine idler pulley, which they changed. Nope. It`s still there.

This screetch has me worried....thought maybe the getrag 360 was pooched for a bit, but it definitely coming from up top, front of engine somewhere.


All fluids are topped up, coolant, power steering, no leaks, haven`t changed the fuel filter in a while .......

Thanks for your thoughts.

 

I'd change the fuel filter first of all. If for no other reason than to protect your pump from being starved of its life-blood.