Any good 850 techs out there? Got a challenge for you

Pumpkinmikey · Post by **Pumpkinmikey** » 15 Jun 2019, 12:07

Hello folks newbie to site so admin send me off ifn wrong page. Have an 96 850 with 200k with fuel injection Problems. I am a good tech.but has me frustrated..crank no start.no codes plugs wet.found intake gskt #1 blown out.replaced. 3 other vacuum leaks fixed.boot new.all tune up parts.timing of belt ok. Got it running by feathering throttle..smoked out neighborhood..bluish white..cleared up ran like a scalded dog.shut it off started right up..NEXT DAY crank no start plugs wet...have checked for dripping inj.and has pretty spark at plug...to quote the beales HELP

Pumpkinmikey · Post by **Pumpkinmikey** » 15 Jun 2019, 12:12

Also checked regulator and replaced maf .temp sensor shows on scanner 72.

Post by **wizechatmgr** » 15 Jun 2019, 13:10

I'm guessing a fuel/air mixture issue - possible massive vac. leak on intake manifold? IAC connected & need cleaning?

What are your pressures after the headgasket replacement? What is the pressure on the fuel rail at this point? Are you 110% sure your timing is spot on, and hasn't jumped?

Post by **wizechatmgr** » 15 Jun 2019, 13:14

Is that a Volvo/Bosch MAF or a generic? The Volvo's have a very bad history of not liking aftermarket parts on the MAF.

Post by **scot850** » 15 Jun 2019, 15:54

A couple of suggestions for you just to help eliminate a few possible issues other than what the guys have suggested.

Sounds like you have a spark (I'm assuming you have verified it at the plug end of the plug lead or spark-plug).

1) Pull the engine oil dipstick and smell the oil to see if it has a strong gasoline odor. If so it could be injectors leaking.
2) Check for loose injectors. Many don't check the 'O' ring seals which if never replaced will have probably failed by now.
3) Appreciate you have maybe not been able to get the car up to temperature, but check the coolant temp sensor. There is a range of resistances at various ambient temperatures it should operate at. Also check it's connector at the power steering pump, again a know age related issue of falling apart.
4) What brand of parts have you used for the ignition parts? As the guys suggested there is a long history of aftermarket (non OEM) parts causing endless issues of P80 model Volvos.
5) Have you checked compression values? These cars can get 'lawnmower syndrome' where they loose compression. Look it up on MVS for solutions.
6) Check the spark-plug leads for damage. I have found a few over the years that have had the leads crushed or cut by poor fitment under the cover at the end by the distributor.

Good Luck!

Neil.

tardcart · Post by **tardcart** » 15 Jun 2019, 18:49

white smoke is coolant or break fluid. plug the vac line to the brake booster and see if that makes a difference.

Post by **Chuck W** » 15 Jun 2019, 22:03

scot850 wrote: 15 Jun 2019, 15:54 check the coolant temp sensor.

This. Primarily, check the connector for corrosion.

Post by **misha** » 16 Jun 2019, 02:44

Try to start it with Maf connector disconnected...make it run first...then proceed with it disconnected and see how it runs.

Good advice about ECT and it's connector for BOTH sides....wiring loom and sensor side.
Both of these connectors for BOTH sensors are prone to failure.

Sensors MUST be oem!
What are the codes?

Pumpkinmikey · Post by **Pumpkinmikey** » 17 Jun 2019, 07:00

No codes.temp sensor shows on my scanner data display accurate..cleaned .head gskt was not replaced..intake manifold gskt was replaced.

Post by **RickHaleParker** » 17 Jun 2019, 07:43

Have you checked for a clogged Air filter and a dirty Throttle Body?
Could there be something in one of the air tubes, like that shop rag that went missing?