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Have a 2.2l sonoma blowing black smoke and idling rough have…

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Have a 2.2l sonoma blowing...
Have a 2.2l sonoma blowing black smoke and idling rough have replaced injectors pressure regulator and plugs wires and map sensor was the only code it had thrown
Submitted: 2 years ago.Category: GMC
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Customer reply replied 2 years ago
Motor also shakes like it's missing while rpms raise have checked for all vacuum leaks all vacuum lines have been replaced. Runs very rough but will not stall and is very had starting have to hold pedal to the floor
Answered in 2 hours by:
3/1/2016
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago
Reggie Whiddon
Category: GMC
Satisfied Customers: 168
Experience: Lead tech at river regions auto
Verified

So the only code it's throwing is for map sensor? What are your fuel trims. Long and short? Whst about coolant temp and intake air temp, and lastly have you Checked the timing chain I've had several where the tensioner broke it jumped a few teeth and ran like crap

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Customer reply replied 2 years ago
only code is for map may have new ones by now have a decent scanner arriving tomorrow. I do not know about fuel trims as I do not have a diagnostic computer capable at this time coolant temp normal as far as intake air temp have not checked that nor the timing chain it was going to be my next step along with testing fuel system for leak down as far as timing chain removing the cover would i be able to tell if it have jumped time? Makes since being that it seems to miss worse when rmps go up and being that the truck has 140k probably due for one anyway
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Yes when you pull cover off you can see therr are dots on thr gears turn crank over and see if they line up if they don't ,your out of time. And yes by mileage your due. Let me know whst you find with timing chain

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Customer reply replied 2 years ago
Just about to check timing chain got my scanner that's OK for a novice shows alot more then some air intake temp was 59 degrees F .. and I was able to screen shot a pic of the timing as I was watching it it was bouncing all over the place for 6.0 to 22.0 I'm a diesel technician so alot of this I'm learning as I go ganna go get dirty hope the screen shot says something that catches your eye . Thanks
Customer reply replied 2 years ago
Looked at timing motors still in time all three marks lineup tensioners definitely was damaged on one of the guides got new timing kit and tensioner to install today
Customer reply replied 2 years ago
Motor was in time but the timing chain was loose compared to the new one I just installed will be putting back together tomorrow have rotated motor 2 complete cycles and timing marks still line up perfentry will let you know what it does after this
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Sir you got it, good job

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Good morning get that timing chain in

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Customer reply replied 2 years ago
just started it still same issue needed to be done but not the problem at hand
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

okay lets back up tell me is it the exact same?

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Customer reply replied 2 years ago
sir, rough idle black smoke out exhaust idles like it missing like it has a huge cam in it lobes almost what a vacuum leak would do bit there's no vacuum leaks
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

okay another thing comes to mind I had quite a few of these the pcm would go bad and hold the injectors open, if you removed all 4 injector connectors and ohm each injector and then put a noid light in each connector with key on and see if light is lit constantly with iey on

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Customer reply replied 2 years ago
Ok will do Imy thinking it's something to do with the pcm I would understand if 1 or so cylinders were wet If i accidently busted a seal installing the new injectors but all the cylinders were wet so I don't think I busted all of them they went in perfectly
Customer reply replied 2 years ago
I have access to lights to test injectors so if each individual one stays on with the key on that's the sign that the PCM is bad also my set only has one per make so I test each individual one with ignition in on position
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Yes Sir THAT Is Right

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Hopefully you Wil find your problem there

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Customer reply replied 2 years ago
Injector ohms are within range and noid test injectors seem to be firing as should each one had same strong constant flash as should
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

And none were on constant, okay since you have no codes i would try unplugging one sensor at a time to see if any has an effect. I am going to look into this be right back

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Customer reply replied 2 years ago
Have gone through that' when issue 1st came all sensors made no difference besides map sensor which had been tested and replaced
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

try unplugging and running what effect

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Customer reply replied 2 years ago
Effect was about every couple rotations it would fire and immediately die
Customer reply replied 2 years ago
Is there a way you know of to jump the coolant temp sensor it's the 3 prong i read it can give hard starts and long cranking? Just a shot in the dark
Customer reply replied 2 years ago
Since it sounds like it's missing what are the chances of a coil or coils going bad and not throwing a code being that the cps sensor feeds them
Customer reply replied 2 years ago
Now i.have a crank no start with still a map sensor code but this sensor is good I believe it's flooding so bad it won't start now
GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

GMorning sorry had grandkids didn't get to get on here let me get u some info hold on

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

on the coolant temp unplugging it would go cold jumping it all the way hot,

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Could you send me some pics of wnat your data is

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

coolant temp, map sensor key on engine off map sensor crank or start, rpm, short and long term fuel trims, intake air temp, tps,

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Is your exhaust possibly restricted

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GMC Mechanic: Reggie Whiddon,
 replied 2 years ago

Hello sir are you still working on this,

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