Poor acceleration, no 'top speed' 92 K1500

[shibbershabber]

Red line. But like I said before, if you are running premium you could actually set it at 2 (the next high point) or 4 (the next low point) initially. Don't forget to disconnect the brown wire before setting the timing!

If resetting your timing doesn't work, time to break out the fuel pressure tester and voltmeter.

Nothing sounds like it's sucking a little too much air (vac leak) does it?

SO assuming I want to run regular, I need to be in that redline. What am I at now -2 degrees?

Now when I reconnect the wire and I am checking the timing, from what I can tell it is about 21 degrees... however the mark moves or wobbles at idle roughly between the green and red lines above. Seems erratic but my idle fluctuates very little if at all.
what could cause the variation, or is this normal?

 

[VorTecxas]

Yes, red line for regular. And yes, you were running -2 after TDC.

Did you restart the truck before rechecking the timing? Though your assumption of 21 sounds about right. Kyle's (my friends) truck runs right around there, it's pretty much at the "top" of the balancer as you're looking at it.

That much fluctuation is not good, you're jumping fire somewhere. Start with your plugs. Make sure they are clean and gapped correctly. Then make sure your wires are not laying on anything or touching each other, that's the most common place for a misfire. Wire separators are cheap and very useful, and even more low buck is zip-ties. The easiest way to see a mifire is to wait until it's dark, unhook your underhood light, and start the truck. Be sure it's dark in the engine bay, no outside light or anything. Trace each wire and more often than not you can see the spark jumping. Also check right at the end of the boot by the plug. I had a bad set of wires and they were jumping fire from the end of the boot to the head at every single plug. If all of that checks out then move on to your coil, check the resistance (though this is unlikely the cause). It could also be the distributor, Kyle's truck would straighten out for awhile and then start fluctuating again. We ended up just putting in new plugs, wires, and coil (he had just rolled 100,000 and needed to do them anyways), and it still did the same thing. Finally just bit the bullet and put in an all-new distributor (got it cheap off of eBay). Viola, no more fluctuating.

This is the distributor we got, it's cheap and it's been very reliable
http://www.ebay.com/itm/220917604282?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

 

[VorTecxas]

And on the fuel note, running premium has many benefits. Since starting on premium and advancing his timing a hair, Kyle tells me his truck feels much more responsive and is getting 16-18 MPG. I started running it about 8 months ago and I've noticed better response and a 2MPG increase (I have the Vortec). Not to mention plugs and intake staying cleaner.

I know you're thinking "it's more expensive". But really it's a minuscule difference for the payoff, have you ever run the numbers? For example, let's say regular is 3.20 a gallon (the average here in North TX). If you put $20 in, you get 6.25 gallons. Normally Premium runs about 20 cents more, around here it doesn't, it's less, but for arguments sake we'll say it does. So premium is 3.40 a gallon. You put $20 in, you get 5.88 gallons, a .37 gallon difference. Using Kyle's truck as a reference, he was getting about 12 MPG on regular and timing at TDC, so on that $20 he could go about 75 miles. Since switching to premium and advancing to 4 BTDC he is getting at least 16. So from the $20 on premium he could go about 94 miles.

Let's look at a full tank. 22 gallons
[email protected]=$70.40
[email protected]=$74.80

Regular@12MPG=264 miles
Premium@16MPG=352 miles

For $4.40 you get 88 more miles.

Now, I'm not saying you will get the exact same results, but this is the result that Kyle had. It doesn't really cost anything since you have to use gas anyways and it's always worth a shot.

Just my .02

 

[shibbershabber]

So I went ahead and bought that very distributor on Ebay...

I put it in and totally messed things up. All because I rushed it and didnt check the position of the original dizzy first.

Now Ive got to retime the whole damn thing.... any pointers?

 

[VorTecxas]

So I went ahead and bought that very distributor on Ebay...

I put it in and totally messed things up. All because I rushed it and didnt check the position of the original dizzy first.

Now Ive got to retime the whole damn thing.... any pointers?

Well that's where it gets fun. Since now you have no idea where TDC on the ignition stroke is, you have to find it. There's a couple of ways. I'll take you through what I would do

First, remove your driver side valve cover. Rotate your crank until the mark lines up with 0. Now, you could be on the #1 ignition stroke, or 180 degrees out on the #6 ignition stroke (since the crank turns twice as fast as the cam). Obviously, you need to be on #1.

Now, start to turn the crank clockwise, if the #1 intake valve moves, you need to go around one more time to 0, if not, you're golden.

Replace your valve cover and stab your dizzy (it doesn't matter where the rotor ends up now as long as wherever it's pointing is where you put your #1 wire). I recommend trying to get the rotor to point at the #1 cylinder, makes installing wires easier since that's how the factory did it.

Now you can set your timing

 

[shibbershabber]

Well... I got it in and got it started...

I got base timing to 0* btdc like it says on the sticker... it is still pretty erratic, and I assume its because my idle is now unpredictable.

when I plug the advance back in its about 20*

The idle sort of cuts out and (since I have the air cleaner off) I can hear the TBI 'gasping' which then brings the truck back to life but eventually it dies.

Looking into the TBI, I can see that the spray patterns arent very nice, and there is some dripping. I assume that this is the cause of my poor idle and dying.

The whole fuel system had been done about 2500 miles ago, fuel pump, filter, TBI rebuild, new injectors & injector wire harnesses... as well as new egr valve, ignition coil, and wires


Is this still a timing issue or is there some other component that is causing this potentially?

I will also have to add that the truck was acting funny before I decided to do the distributor... random unexplained dying at idle being one of them, in addition to the issues pointed out in my OP.
I cannot see there I may have knocked something off or loose in doing the dizzy, but it is decidedly worse that it was before I started.

 

[VorTecxas]

That's a fuel issue, no doubt. Even though your CEL may not be on, see if you have any stored codes. OBD1 is bad about that

And I'd start inspecting parts real close. Even might remove and clean them to be sure

 

[shibbershabber]

Well I do have a code 42 in there.

which refers to an issue with the EST system... which would make complete sense.


Time to hit the books!

 

[VorTecxas]

Git 'er dunn!

 

[shibbershabber]

Alright! Ive looked it up in my factory manuals and I have a clear path to solving this!

BUT, it has to wait until next week! Stay tuned!

FWIW, these manuals are the greatest things I have ever seen! Step by step troubleshooting for every code possible!