Runaway Throttle, Blue Smoke, Shut Down

[vliposky]

Engine starts very briefly, revs way up with lots of blue smoke and then shuts down... 94 Chevy 2500 4WD Suburban with 140,000 miles.... Anybody know what fix is.... or what possible causes are... or best sequence of checking out in decending order of cost (ending with replace engine) ? Sure would like to have my ride back...

[Chevylover]

Blue smoke is a indicator of burnt oil. So the engine burns oil, but where does it come from ? What about the SES light ? Any Codes ? How does the began ?

Could be a lot of things : PMD, piston slap, worn piston rings, hole in piston, Injection pump and so on.

Check codes and explain exactly how it began.

Cu,
Sven

[vliposky]

Thanks for your thoughts....
Drove prox 10 miles - all well. Parked one hour... Started, drove one half mile and engine started to rev and speed up on its own.... It shut down.... Tried to start to get off road... Would start momentarily, rev up, make blue smoke & shut down.... over & over til towed off road... Saw no words on instrument about codes etc... Took to mechanic who said when He started it, revved up & made only black smoke...(filled shop) and shut down... Says some variation as a result of "pecking on pump)... Injector pump was replaced by GM at 118,000 miles.... Currently engine has 141,000 miles on it.... What would YOU do next & after that etc...? (I do not trust this small town dealer especially with this 1994 diesel...)

[vliposky]

Mechanic says doesn't think it is burning oil since no oil residue in exhaust pipe etc... (One guy said possibly bad turbo seals would allow engine oil to burn.... Would seal go out that instantaneously ??)

[Chevylover]

At any time, blue smoke is an indicator for burnt oil. White smoke is burnt coolant and black smoke unburnt diesel fuel.

So it could be that the PMD is the reason. IS you PMD mounted at the OEM position directly to the pump or do you have it relocated with a PMD-cooler ?
If it is at the pump, i would seay try if you can one to test and if the symptoms are gone that's it. First i would check if there is oil at the intake hose directly mount at the turbo. If you CDR-valve is defect it will let oil breathe fromthe crankcase to the turbo inlet. But as you mentioned the typical PMD probs : stalling, BLACK smoke and shut off again - it seems really that you got a fried PMD.

That would be the "cheapest" thing, because the other reasons would be much expensiver like turbo damage, piston damge or something else.

On a 1994 You can check the errror codes by youself. Check it out here :
How to read the codes (http://www.kennedydiesel.com/readcodes.html)

FSD / PMD Cooler (http://www.ssdieselsupply.com/category_6_FSD_HeatSyncs_PMDs_and_Resistors.html)

CDR Valve (http://www.ssdieselsupply.com/category_19_Emission_Control_Components.html)



Cu,
Sven

[sixnickel]

My guess would be the PMD/FSD My 99Burb did the same thing and mine was mounted on a FSD cooler with about 30,000 miles on it. After about 2 hrs of checking every else out of desperationI pluged in a good used FSD if flipped over and started. That driver has been on it ever sence (about 2 years}and it has not missed a beat! Good luck!

[vliposky]

Thank you, guys....

More helpful than you can imagine...

Special thanks to Sven.... The how to read codes is going to be IMMENSELY helpful....

New idea... Any place to Rent or Borrow good PMD?

[Chevylover]

Thank you, guys....

More helpful than you can imagine...

Special thanks to Sven.... The how to read codes is going to be IMMENSELY helpful....

New idea... Any place to Rent or Borrow good PMD?


No Problem !

Rent or borrow a PMD ? I don't know. If you were located in germany - i got a spare in my truck, but in the USA ? The only thing, to be on the cheapest way is to check at Ebay.com.

PMD (http://motors.search-desc.ebay.com/PMD_Car-Truck-Parts_W0QQcatrefZC6QQcoactionZcompareQQcoentrypage ZsearchQQcopagenumZ1QQfcclZ1QQfclZ3QQfgtpZQQfmmdZQ QfmmkZQQfposZQ5AIPQ2fPostalQQfromZR2QQfrppZ50QQfso oZ2QQfsopZ2QQftrtZ1QQftrvZ1QQftsZ2QQfyhiZQQfyloZQQ lopgZQQmppfqyZPMDQQsacatZ6030QQsadisZ200QQsaprchiZ QQsaprcloZQQsaslcZ2QQsbrftogZ1QQsofocusZunknown)


FSD (http://motors.search-desc.ebay.com/search/search.dll?sofocus=unknown&sbrftog=1&catref=C6&fcl=3&frpp=50&from=R10&fccl=1&mppfqy=PMD&satitle=FSD&sacat=6030%26catref%3DC6&fts=2&fmmk=&fmmd=&fylo=&fyhi=&mppfqy=PMD&sargn=-1%26saslc%3D2&sadis=200&fpos=ZIP%2FPostal&ftrt=1&ftrv=1&saprclo=&saprchi=&fsop=2%26fsoo%3D2&coaction=compare&copagenum=1&coentrypage=search&fgtp=)

They starts at 70 US $.


Cu,
Sven

[vliposky]

Would engine problem codes tell if PMD is bad? If no specific code for bad PMD, what would codes likely read out if it WAS the PMD?

[Chevylover]

Code 35 or 36 is a PMD fault.
Code 17 or 18 is a massive injection pump failure.
Code 78 is wastegate solenoid fault.


Cu,
Sven

[vliposky]

What do letters PMD stand for? What does the device do? Could a defective PMD cause unexplained, sudden hi revs?

While I am at it, what do letters FSD stand for and what does it do?

(I bet Sven knows)

[Chevylover]

What do letters PMD stand for? What does the device do? Could a defective PMD cause unexplained, sudden hi revs?

While I am at it, what do letters FSD stand for and what does it do?

(I bet Sven knows)



PMD - Pump Mounted Driver

FSD - Fuel Solenoid Driver

PMD / FSD is the same thing ! The little black box (big as a deck playing cards) mounted on the driver side of the injection pump.

Cu,
Sven

[carlos]

keep in mind that the code 78 could not be your solenoid check all vaccum lines from the vaccum pump to the solenoid and from the solenoid to the turbo wastegate you could have a broken pump or evena broken hose. I foung ou the hard way.

[vliposky]

Everybody I talked with never heard of PMD causing runaway throttle - hi revs- but that is what it turned out to be! (Borrowed a known good one and with the new PMD engine now runs better than ever!)
Thank you Guys!