Good afternoon Enthusiests,

I'm sure someone must have already asked this but, is it normal for my engine to quit running when I run this test and get a no errors found test result?

Thanks in advance.

Dean

 

What engine are we talking about? 7.3? Does it exhibit any drivability issues?

 

We are talking about the 7.3. No real drivability issues though, I fear I may have compromised one of the head gaskets when I installed the heads. On start up, I see 2 distinctly different colors of smoke from the exhaust. I see what appears to be a blue or light grey smoke along with the expected black smoke from the unburned fuel. It's the blue/light grey smoke that concerns me. So I ran the cylinder contribution test and when I do, the results are the engine shuts off and ForScan shows no errors found. I just want to know if those test results are normal.

 

That is not what I have seen happen.

 

What has been your experience with the cylinder contribution test?

 

It just shows which cylinder is low or shows all normal. Then I close the test and go on to the next.

 

the grey/ blue smoke you are seeing is usually raw unburnt fuel and will burn your eyes as well as kill living things like flowers/ bushes... I have that with my truck but it is because of my larger injectors. I imagine faulty injector orings could have similar symptoms

I see you have 238/100's...that could/ would explain it.

also if you just did work, you should know it will take some time to get everything out of the system and clear up, IDK.

I don't run the contribution test because it's worthless IMO and give false info. I have run it in the past but don't even recall the whole operation of it. I want to say it should run through and give results. I also use AE rather than forscan but should be the same. I faintly remember a buddy having issues running the test on his snap on during some diags but it's been too long to remember correctly.

if everything is normal besides the smoke, I think it's normal for your injectors and especially the colder weather. However it should pretty much clear up after running at operating temps typically. Mine used to clear up but this year it isn't...I probably have issues of my own. Also, typically if I switch back to my stock injectors, it all goes away. that's how I know it's the injectors.