He guys, I’ve been having a problem with my 850, we have been doing all sorts of stuff to try and figure it out but we still have no clue what is wrong with it. Before we take it somewhere professional to check it I figured I would ask you all.
the car:
Its a 1996 Volvo 850r with the 2.3 turbo. It has been tuned to have the 2.4 camshafts, larger injectiors, and no catalytic converter.
whats wrong:
The engine spins without strain on the starter motor so it isn’t a low battery and it simply will not try to start. The closest we have gotten to it starting is a pop from the headers when the motor starts spinning. Whenever this pop happens a bit of smoke comes from the header at cylinder 4.
some background:
I had the car working for a while, it was purchased with a lot of issues and we resolved most of them. Before we put it in the garage the most recent time the car would be able to run and drive. Some of the problems experienced when using the car before it was put on jacks was that when I would go from a stand still it made no power until 2k-2.5k rpm but made the standered 200+ hp when it was between 3k and 5.5k. After 5.5 the engine would sputter/backfire to the point that the car rocked violently forward and backward. Another problem was that when you where at an idle the car would emit a lot of white smoke from the exhaust, this would get significantly worse if the A/C was on, it would also blow the white smoke out in large quantities when I would let off after pushing the petal to the floor. other then that it drove normally and could go very fast.
I am at a loss as the engine spins but does not even try to fire or anything of the likes, it just spins.

*Edit*
problem resolved, combination of a lot of things
before it broke completely, we had bad timing and the spark gap was way too large hence no power low end and a sputtering top end. Finally broke because of bent valves, guess we bent them when checking timing because all 10 exhaust where bent. Fixed now and runs like new!!

 

The early (pre 99?) cars have hydraulic lifters/tappets. If you start one of those and move if a few feet, then turn it off - it will have "no compression" the next time you try to start it. The starter will spin the engine over too easily, too fast, like there is no compression. Very frustrating -

Many a car was towed in to my shop for that symptom during the years that was a common car. Some will say "oh the cylinders are washed down with gas, so let's replace x" or "the lifters are sticking so let's replace those". Or some say "needs new plugs, needs oil in the cylinders, needs valve job, needs piston rings, needs a new Johnson rod, or a right hand clevis link".

The solution - fully charge the battery and attach a battery charger, push the accelerator pedal to the floor, Turn the key to the start position and hold it there - 45/60/75/90 seconds (much more than you are comfortable with) and the engine will start to fire on 1/2/3 cylinders - once it fires on enough cylinders release the starter and rev the engine up. Warm it up, drive it around, turn it off and it will start normally the next time. Just don't ever start the car, move it 20 feet and turn it off again without warming the engine up.

How do I know - I have done this hundreds of times when cars were towed in for "no start, spins over but sounds like there is no compression". And if my techs got one of those tickets they would want to sell some of the list above - although I still don't know what a "Johnson rod" is.

- try my solution first - it works

 

google "lawn mower syndrome" - which is what hoonk is referring to. RobertDIY has a vid on Youtube discussing. If you got fuel pressure and spark, then this talks to compression...

 

So, the trouble was, bent valves. I didn’t think it was but they where bent when adjusting timing with a wrench and no starter interference.

 

Wow! Thanks for the update.