[trevorbpeterson]

Hey everyone, I apologize if im in the wrong neck O' the woods with this but I am relatively new to the forum scene so please let me know if i should be elsewhere.

My problem is as follows;

I had a 1990 Chevy cheyenne 1500 2wd single cab long box with I believe either a 5.0 or 5.2 litre V8 (it was some sort of crate engine the previous owner dropped in)
she ran flawlessly, just had the get up and go factor unfortunately the transmission was in a bad state so i decided to do a transplant.
i found a 1989 gmc sierra 1500 4x4 ext cab long box with i believe a 5.7 that somone spun a bearing in, the truck ran but was on its last legs when i bought it.
My plan was to put the engine from my cheyenne into this sierra. before the swap i tested the following;
My 5.0 v8 ran flawlessly (as stated above)
the 5.7 ran like crap but still ran
the 4x4 in the sierra worked 4H and 4L
all the lights and turn signals also worked in the sierra

I took them to a mechanic (turns out it was a reputedly shady one, but i was unaware) and had them perform the swap got it out several months later....
when i tested the sierra (with good engine "installed") i ran into the following issues.

-The turn signals dont work, quick spasmodic flashes and little to no light up. same with brights and headlights in general
-the engine would start but would then choke and die a few minutes after, and not restart very easily.
-the 4x4 does not engage at all.
when i do get it running i get black smoke and rough idle as well as very low power (cant go above 30 with out some serious finessing of the pedals)
and then as i stated above will randomly quit.
-as well as various engine mount bolts and misc items loose or not connected/exhaust plugs missing etc

I know my engine was in good shape as i had driven lots with it before the swap, and the gentleman i bought the dead sierra from took good care of his truck as it was his daily until the bearing spun.

my question is this, since everything ran beautifully before the swap, i cant help but think something was screwed up in the surgery suit....
anyone have any ideas on what could be the issue? what i can check/do?

Sorry for the long winded question and I appreciate any and all feedback

 

[Azcheby]

Id start with bad grounds or a lack of especially if you have found missing or loose bolts. That in itself would cause all kinds of screwy issues especially with FI. Fortunately it looks like both trucks regardless of a 4.3 up thru 5.7 use the same engine ECM. Regarding the 4x4, was the 4x4 truck a manual shifting or the push button on the dash? Back to probably lack of hooking things up or disconnected linkages possibly. IIRC either system used a electric shift motor on the front diff, but one has manual linkage to the T case if its floor shift type.

 

[trevorbpeterson]

Id start with bad grounds or a lack of especially if you have found missing or loose bolts. That in itself would cause all kinds of screwy issues especially with FI. Fortunately it looks like both trucks regardless of a 4.3 up thru 5.7 use the same engine ECM. Regarding the 4x4, was the 4x4 truck a manual shifting or the push button on the dash? Back to probably lack of hooking things up or disconnected linkages possibly. IIRC either system used a electric shift motor on the front diff, but one has manual linkage to the T case if its floor shift type.

It was shift lever on the floor

 

[nealinator]

There is just no telling what all was done. You will be paying someone else a bundle to straighten out the mess or spending lots of your time going through it.

 

[trevorbpeterson]

There is just no telling what all was done. You will be paying someone else a bundle to straighten out the mess or spending lots of your time going through it.

that's what i was thinking, in your opinion would it be worthwhile to straighten out, seeing as I've already gone this far? or should i just cut my losses and buy a new unit

 

[nealinator]

I sure can't honestly answer that with the given info. I have been known to dig in and deal with something when I probably should have cut my losses. Just depends on what it means to you.

 

[trevorbpeterson]

alright, thanks guys ill give it some thought