Draft p80 Master Volvo No-Start flow chart..please add to..

Post by **abscate** » 27 Jul 2014, 04:23

Intent here is to give a quick referal to no-start posters on how to get going again. Please edit by copying and pasting here, and of course, Roberts video will be a natural addition!

1 Compression check
Tests rings, valves for correct operation. Ok to skip if car has long history of running well, but if other items check out , break out the compression gauge.

Tools needed
Typical pressures

2 fuel delivery/induction
Check fuel pressure at rail..50 psi, holding 20 psi after 20 minutes
Most common no starts are fuel pump relays, wiring.
Link to fuel pump jumping procedure.
Remove plugs ..are they wet with fuel? Describe plug condition
Disconnect MAF (link) and try.

Vacuum leaks suspects
Turbo hoses, especially at intercooler
Idle air control valve
Vacuum elbow

Tools needed

3 spark delivery
Evaluate condition of cap rotor wires plugs. How old are they?
Remove plug, ground base, crank,evaluate spark..yellow or blue? Is it regular interval?
Check connectors at cam and crankshaft position sensors (link)

Tools needed:

4 valve timing and belt
Remove top engine cover and observe timing belt motion. Confirmed with compression test numbers.

Tools needed:

5 starting circuit
Age, condition of battery?
Ground lead check, especially under battery and master ECU, engine to body ground straps
Immobilizer problem, if applicable

Tools needed:

6 ECU
It's not your ECU, trust us.

Tools needed: Faith.

Post by **rspi** » 27 Jul 2014, 06:20

Maybe reorganize for the most common or easiest things first and work towards the harder things that require tools that most people do NOT have like compression gauge, fuel injector test lights, etc.

Post by **RussB** » 27 Jul 2014, 07:02

check for spark

check for fuel

check compression...

in that order

Post by **abscate** » 27 Jul 2014, 08:51

Agreed, but I think consensus is fuel pump, relays are the number one cause of no-starts.

The reason I put compression on top is it forces the discussion of engine history. Maybe we will make it number 3 with some preamble.

Post by **JimBee** » 28 Jul 2014, 06:43

A terrific idea! Several members tried to get a check list going a few years ago but it fizzled. The db is easily searchable (thanks Matt!) but knowing which questions to ask, based on symptoms, explanations of engine logic and which tools you'll need could make the site even more efficient and the vehicle less mysterious.

Right at the top might be: Does the engine turn over? If not, battery check (standing, engine off voltage?). If battery is okay, wiring to starter? Clean terminals? Check starter? Hot wire starter?

Thanks for doing this.

Post by **abscate** » 28 Jul 2014, 12:09

I might be wrong on this but I think the logical split is the

1. Engine doesn't crank thread

And

B. Engine cranks but doesn't start thread

These can ultimately be links in the master

iiii) help I can't get to work, play, Dead Concert......thread

B) is the most complex I think

I'm trying to encourage people to copy what I posted as a starter and then edit as they see fit. That will help this converge

The other thing to develop is when you get the (rare) frustrating "short of information" no-start thread you can push here for specific answers. It gas gotta be frustrating for you gals/guys who know these cars well to have to repeat the same stuff more than a P0455

Post by **shaker_chi** » 28 Jul 2014, 17:07

Is there an easy way to check the ECU. You say it's not the ECU, but mine went out on my 1994 850 n/a and it took me about a month to finally pick one up on ebay and see what happened. It started on the first turn and I had to run it for about an hour because of all the fuel I dumped into the engine from all the previous no starts. Also had to replace an oxygen sensor. Anyway, moral of the story is that do NOT rule out the ECU.

Post by **abscate** » 02 Aug 2014, 05:07

There isn't an easy way to check an ECU. But, ECU failures are rare and almost never a cause of no-starts. I think people calling them computers makes them think they are unreliable, whereas in fact they really are embedded microprocessors with high reliability.

ECUs won't be covered in this thread , other than perhaps an early preamble on history.

Das_Rah · Post by **Das_Rah** » 12 Aug 2014, 09:10

You read my mind! This is the exact info I was looking for this morning, thank you. I love this site

Post by **JDS60R** » 12 Aug 2014, 12:13

RussB wrote:check for spark

check for fuel

check compression...

in that order

I agree with Russ. I've seen hundreds of these and misfires and no firing is what we see most often.
If you want to make it useful post the methods of testing attached to solutions. (ie Listen for pump hum when key is turned or have a friend listen while you turn key - if no hum check fuel relay located at x (add pic) or add jumper to check for hum). When posters can find evidence of failure they will follow the correct method to repair/replace the part.

This is especially true for those who do not keep there car at Stage 0 as those who do are updating ignition components, oxygen sensors etc before failure or poor performance and get to avoid bad cat converters, internal piston and valve deposits, poor fuel economy etc.

Its always helpful to ask before doing anything.
Did you read the codes?
Are you at Stage 0? (explained as needed)