Intermittent hesitation on 96 850 GLT

mtfrith · Post by **mtfrith** » 16 Mar 2009, 18:50

Three week's ago I replaced the spark plugs, which seemed to solve a lack of acceleration problem. Two days ago a similar malady occurred. While the car accelerates as normal, it intermittently hesitates or feels like its "missing".

Also have noticed that the car will not start on the first cranking cycle at ignition. However, it fires immediately on teh second cycle.

I removed the distributor cap and rotor - which appeared to me to look good, very little corrosion. Also replaced the fuel filter today. The fuel pump was replaced 12 months ago.

What do you think? I suspect iginition wires, rotor and cap.

Post by **MadeInJapan** » 16 Mar 2009, 19:13

Depends....what plugs did you use and what gap?
Your model calls for 0.028 inch gap and we have all had similar experiences when we've used Bosch Platinum plugs- did you use these? Your best off with regular Bosch copper (cheap) plugs or Volvo non-turbo plugs.

Mike-Halewai · Post by **Mike-Halewai** » 16 Mar 2009, 21:39

I have the same symptoms.. replaced the temp sensor as a couple of posters thought this would help.. no dice though.

I've got NGK platinum plugs in, will this actually cause an issue with this though? hmmm? What type of plugs should I be running in a '94 850 Turbo Wagon??

I might as well give it a try...

Post by **MadeInJapan** » 16 Mar 2009, 21:56

Turbo or not, our cars love either Volvo plugs for your specific vehicle or just cheap Bosch coppers- make sure and get the gap right- this makes a huge difference (even if they say they come pre-gapped). Our cars do not like Platinum plugs of any kind (I've just read lots and lots of posts about these causing idling, misfires and hesitation issues, especially after 3 or 400 miles (seems good at first but then performance starts to go).

C@lvin · Post by **C@lvin** » 17 Mar 2009, 10:31

I had a similar issue on a 96 850 T5 after changing the plugs. I knew they were gapped right cause I'd triple checked them before installing.

Thinking that it couldn't be the brand new plugs, I checked the wires, the distributer, points, etc. Went round and round for two weeks and two garages couldn't isolate the problem either.

When I finally decided to go back to square one, it
turned out one of the plugs' ceramic insulator was cracked.

Post by **jblackburn** » 17 Mar 2009, 12:29

I have NGK Platinum's in my T5 S70, gapped correctly, for about 10,000 miles, and I haven't had a problem at all running them in mine. I can't say the same for the Bosch. New ignition wires may be a good bet; I was able to tell a huge difference in smoothness of acceleration in my 20-year old Honda when I changed out the wires & distributor cap. I wonder if it could also be your injectors might just be gummed up? Have you tried seafoaming/fuel system cleaner on your car?