96 GMC Sierra "skips" when shifting

[bcrooms]

I did install a K&N filter on the truck. Since you mentioned a leak around the intake gasket, I'm wondering if it is loose. I remember it giving me fits during install. The stock air intake is a breeze to put back on, I can swap them out again and see if the problem goes away.

 

If not, then it may still be around the intake area but not directly related to the aftermarket K&N.

 

I do have odd problems with electrical stuff inside the cab such as radio reception and if i plug in a iphone charger in either of the two charging outlets (not cigarette outlet) my radio will stop reception.

 

I haven't noticed any odd lighting problems though.

 

Just throwing out more info to you to get the best idea of the situation.

[Jsdirt]

Since you have a K&N, check your MAF sensor for oil contamination - common problem. A quick Google search will show you pics of what to look for.

[bcrooms]

Will do. thanks for your help on this. It's been an aggravation to say the least

[bcrooms]

I checked for vacuum leaks around the intake and the manifold last night, I did not have any success finding one.

 

I did go ahead and change out the fuel filter, but it didn't help as much as I thought it might.

 

Can I just get a code reader at AutoZone or does a mechanic need to use a real deal scanner on it?

 

The truck seems to get worse as it gets warmer.

[Jsdirt]

Any cheap scan tool can show live data - I'd highly recommend grabbing your own.

 

The ones the parts stores use typically only read & erase codes - not much else.

 

Getting worse when warm rules out the intake gaskets as a problem, and it sounds like you verified that already anyway. Usually things that get worse with heat are coils of wire, like an ignition coil. Hate to have you throw parts at this thing without knowing for 100% certain, but the only way you can be 100% certain is by hooking up a scope to the ignition primary or secondary. The waveforms will show if spark is dropping out randomly.

 

Most private garages (but not all) have an oscilloscope, or a scan tool with one built in, like the Snap-On Verus. Might be worth paying one for diagnostic time to hook it up and have a look. Would be money well spent at this stage.

[bcrooms]

I do have a buddy that is a top notch mechanic that will do a diagnostic scan for me, free of charge.

 

I just wish I knew enough to fix it myself, but I know he can figure it out.

[Jsdirt]

Nice - keep us posted as to how it turns out.

[bcrooms]

Well it didn't turn out as I had hoped. my mechanic buddy didn't find and evident problems.

 

He drove it many times while he had it for atleast a month and he could only get the truck to show the issue a few times.

 

I'm still wondering if there's something wrong with my intake. I may try re-installing the stock unit and see how the truck performs vs the K&N.

 

This is blowing my mind and the mechanics so it's definitely not making any sense as to what it could be.

 

I honestly just wish something would break so it would be an obvious fix.

 

I still need to replace the front end and transfer case fluids. I have done the transmission and rear end so far.

 

It is due for new shocks all the way around as well.

[Jsdirt]

This is reason #1 why I hate all vehicles built after the 1995 model year. If I'm honest, after 1984 ...

 

They can be a royal PITA to troubleshoot.

 

 

Is the check engine (MIL) light on? Usually if the problem is bad enough to feel, it'll throw the light on after a few hundred miles or so.

 

Throwing the stock parts on is definitely a good place to start - at least you'll be able to rule those parts out afterward, one way or the other.

 

Another thing to keep in the back of your mind - if that has the notorious spider injection system, I'd be looking at that next if all else fails.

[bcrooms]

The only light that is on is the ABS light and its been on for years.

 

I'm thinking it may even be a sensor or the regulator on the transmission. My father-in-law had an older Chevrolet once that had similar issues and it just need a new sensor

[Jsdirt]

Shift solenoids fail on those all the time, but that will cause the trans to be stuck in one gear, and throw the light at the same time.

 

Wouldn't hurt to check for communication or body codes with a high-end scan tool - those codes won't set a light, and you'd never know they were there without the scanner.

[bcrooms]

Yeah I was under the impression that my buddy was gonna do a diag scan with his high end tool but I don't think he had time to spend on it and not charge me.

 

He stays covered up with customers.

[bcrooms]

After researching the symptoms I'm having with my truck and listening to friends who have had transmission problems, it sounds like my transmission may need repair or at least the torque converter.