Chevy & GMC Vans

This will go long; sorry, it’s how I write…

RANT ON :

Current problem child:
99 Astro. LS Pass. AWD. 105 K. (Bought it w/100 K on it.)
Had been running a bit ‘funny’ since purchase: hesitations / VERY sluggish response on jamming the pedal to get on the freeway.
Intermittent, came and went; attempts to duplicate causes produced no joy.
I drive it aggressively, as needed. Lots of freeway miles; run it around 75-85 most of the time.

Ran two doses of GM poppet cleaner through 2 full tanks of gas; about 2 weeks apart.

Slight (improved) change, but still occasional sluggard response.
NOT good getting on to the freeway in heavy traffic at Ohhh dark thirty.

Changed out the fuel filter.
Did not release pressure via the relief valve.
Just slowly undid the connections and let it bleed out.
Better, but still sluggardly at times.

Van sat for 5 days while I was off moving my daughter out of state.
On my trip home, made it over Altamont Pass (Livermore to Sac, CA) w/no probs at 80 or so.
Heading on to the 5, the critter started huckle bucking; losing power gradually.
Made it off the 5; got a couple backfires and a nasty snarky odiferous sulfur gift.
Not a good thing at 11 pm on a weeknight, 100 or so miles from home…
Let it sit for some minutes, crossed fingers and fired up.
Ran ‘fine’; no probs, no hesitation, nothing…gingerly limped home…whew!

Let it sit overnight; now running rough; slight/occasional misfiring/hesitations.

Got a ScanGuageII.
Trouble codes: P101, P1345.
Cleared 101, hasn’t come back.
Cleared 1345, keeps coming back.

Checked out 1345 on the net.
Freakin’ CRANKSHAFT???
HUH???

Anyway; I’m up for shade tree repairs/renovations.
Dollars being in shorter supply these days, and all.
Rather not have to go dealership for fixes, but will if I must.

Can ya help a bro out?
Suggestions?

No Peter, the hand grenade/c4 option won’t work right now…
Driving the back-up, ol’ paint 94 Safari while I while away my idle hour trying to figure the 99 out…
GOOD thing I didn’t sell the 94 yet, as I was planning…
The damn 94 runs better than the 99; it’s just a lot more cosmetically beat up and I bought the 99 to ‘upgrade’…not working out so well, at the moment…

Thanks for surviving my rant!

Sorry you've had issues...Hope you feel better...Wish I could help...NSL...Good thing you kept your old van. Wish I would have kept mine...Good luck!

For starters we need to know everything you've done to try and cure the problems.

Haven't driven it into a freeway abutment at 90... ](*,)

I've done nothing but drive the 94, buy a ScanGaugeII, get codes, find out how much a new cat costs, how much a new MAF sensor costs, etc.

Bought the van in late Dec.
My Christmas present to myself.
Owner said he'd had it tuned up (plugs, cap, wires, etc.) recently.
It ran decently enough, at the time.
Yeah, more finicky than my 94, but acceptable.

I figured part of it was the fuel injection sys and fuel filter.
In mid Jan, I ran 2 courses of GM poppet cleaning juice over a two week period.
Fuel filter change out late Jan.
Not much change in the finicky bits.

SES light has been on and off since I got the van.
I know some of the things that trip the light are momentary spikes on a sensor or 3, so it's not something I've been overly concerned with.
Hasn't stayed on at each start up until after my adventure.

I'm leaning toward:
Could be a crisped cat converter.
I've never had one make a dull popping noise and smell like a bad egg.
(Happened during my drive home from Livermore.)
I haven't crawled under yet and banged it to check for marbles.
A dead cat might create a bit too much back pressure for the system.
And given the computerization factor, could result in wrong signals to the fuel sytem.

Given that these computerized rigs have their notorious glitches, I'm not real interested in plunking down precious change on something that won't fix the prob.
I've done the 'changed out this, changed out that...NOW what??? run around and pull my hair out' with more than one vehicle, and not just a GM product.

I'd rather not have to go to a dealer for a fix.
The closest dealer in my area doesn't have the best rep as far as 'repairs' go...
If I MUST, I'll find one a bit farther out and get 'GM only' repairs done there.
They charge the goin' rates for NorCal. #-o
I don't have a personal mechanic who I KNOW will find the bug and fix it.

Forum folks who've had some experience with this might just save me and my wallet some serious headaches!

my quick guess would be plugged/dead/melted cat ... and/or bad O2(s) can contribute to a killed cat

check the cat when the system is HOT.. not for marbles... for how much heat there is before vs after (should be about the same) ... if it's already broken up inside and melted from the heat.. it could be a solid chunk now...

ensure the cap/rotor/plugs were done... it's easy to say, not see LOL

as for the P1345 "Camshaft To Crankshaft Position Correlation Fault"

Maybe a sensor (camshaft or crankshaft position) is failing or has a bad connection at the plug?

pj wrote:This will go long; sorry, it’s how I write…

RANT ON :

Current problem child:
99 Astro. LS Pass. AWD. 105 K. (Bought it w/100 K on it.)
Had been running a bit ‘funny’ since purchase: hesitations / VERY sluggish response on jamming the pedal to get on the freeway.
Intermittent, came and went; attempts to duplicate causes produced no joy.
I drive it aggressively, as needed. Lots of freeway miles; run it around 75-85 most of the time.......Can ya help a bro out?
Suggestions?

No Peter, the hand grenade/c4 option won’t work right now…

There is no way that a newbie would know just how sarcastic an sob I really am. Not this quickly. I dunno if I should be proud or shamed...

The blocked cat makes sense, though I dunno how easy it is to block our newer version cats. They're basically a straight-thru design....

Crank sensor wire could be shorting or open-circuiting intermittently as well. You really should crawl underneath and see if anything looks cut/damaged

When the cat failed on my 98 the van had no power and I had to tow a trailer about 200 miles! ](*,) It was very loud too and you could definitely tell it was plugged. I double checked for a bad cat by having the van running and gently tapping on the converter. It rattled so I knew there were pieces in there instead of a solid piece.

P1345 "Camshaft To Crankshaft Position Correlation Fault"

Could also be a stretched timing belt/chain

I'm going to second checking the cap, rotor and plugs. Check for corrosion, carbon traces, and look and see what the plugs look like. It doesn't cost you anything to look, and they can cause no end of problem, especially a cap and rotor that are not genuine GM parts. I, like many others, tried an after market cap and rotor, and it lasted one year, just like everyone else who had done so said it would. Since someone else did it, who knows what he used, not to mention checking these things can tell you a lot about how things are running, in particular the plugs.

zombie i was thinking about that too but 105k seems to soon for a timing chain to give up the ghost, But that code sure sounds like it.
i've had to change my Crank Position Sensor was giving me a P0336 felt sluggish occasionally and once in a while when you stepped on the gas would slowly creep to speed other times would get up and go.
considering the code you have you might want to check both CKS and CMS if either have failed or come loose it could generate this code i think (never seen this code before to be honest)

Cobra wrote:zombie i was thinking about that too but 105k seems to soon for a timing chain to give up the ghost, But that code sure sounds like it.
i've had to change my Crank Position Sensor was giving me a P0336 felt sluggish occasionally and once in a while when you stepped on the gas would slowly creep to speed other times would get up and go.
considering the code you have you might want to check both CKS and CMS if either have failed or come loose it could generate this code i think (never seen this code before to be honest)

It is possible though. If the van was driven like hell before it could definitely be a timing chain :-k just a thought

Hey, thanks for all the suggests, guys!

I'll get my tail out and under and see what's up (or down).
As you can probably tell, I'm not a fan of the computerization involved.
Necessary evil, I guess; you just end up having to deal with 'progress'.
Might as well try and have some fun with it, while not pulling my remaining hair out.
I sometimes wonder about the GM engineering 'geniuses' who designed the layouts of some of this stuff. ](*,)

Oh, Petester...
I may be a 'newbie', as far as post #'s go...
I do read here a bunch checking data/info for this and that.

As one jaded, sarcastic sob to another:
Yes, you should be proud.
Ascerbic wit frequently goes over many heads.
And yes, you should also be shamed.
I'd pay money to see that shamed look on yer mug!
Priceless!!!

Now git off my lawn!!!

Ascerbic wit's a good thing, right?

While you're in there doing the tuneup stuff add a set of high end plug wires. Anything less will just fail early.

my money is on a bad cat.