When driving my automatic 96 850 Turbo I have been getting a significant hesitation - a quick drop in all power to the engine, causing the front end to dip before kicking back in. I only encounter this as I am trying to get on to the interstate or pass a car quickly - I try to drive easily with the car - but it always happens at 3500 RPM.

I do have a small leak in my fuel tank at the heat shield but have not had a chance to get to the dealer to get it fixed (warranty recall). That may or may not be part of the problem.

No codes showing up.

Any ideas? Thanks in advance.

 

sounds like a problem with the turbo, as i think 3500 is when the turbo should start boosting.. not sure.

 

maybe get a video up?

it could be cutting fuel because of leak?
when was last tune up?

wait for experts.

 

What is the condition of your CBV diaphragm?

 

I have not checked it --- I just had to look up what that stood for. Ha! I'm a newbie with more curiosity than knowledge.

Where is that located in the engine? I have a couple of the generic manuals but don't see that listed....

Thanks for the info and patience

 

I will try to get a video of the error -- It had been about 15,000 mi. since the last full tune - new plugs and wires, serp. belt, distributor, fluids, and some other general maintenance - That was right before I got the car so I did not perform the maint. but I do have the receipt from the service.

I have kept up with small things since then, but no major work.

 

It is located on the turbo under a triangular looking plate. Only way to check is to remove it, but make sure you have a ratcheting 10 mm wrench and jack stands. Bottom bolt is reachable from the top, but so much easier from underneath. Here's IPD's link to their replacement version. Either use this, a Mitsubishi replacement, or something comparable. Volvo to my knowledge does not offer the diaphragm separately. Of course, it could be something entirely different, either way good luck.
http://www.ipdusa.com/product.asp?st...hStartRecord=1

 

Thanks for the info - I will start by checking that and some new plugs.

 

you should not need new plugs. you could check the gapping if you want though.

Example of the CBV

 

TIPSP - thanks for the photo and the information, I have a feeling I'm just getting started.

 

Sounds to me like fuel cut off.