Throwing this out there- engine help

[drglinski]

Hi guys.

I've got a non-cub cadet engine related issue on my truck, and I was wondering if someone could help point me in a direction to look/consider before I start throwing parts and $$ at a problem that might not need parts. Here's what I'm going through:

1997 S 10. 4.3 liter engine. 150,800 miles. 2 wd.
Outside temp: just under 20 degrees F
New battery: January 2015
Fuel: 3/4 full tank

I had trouble getting the ole girl going today leaving work. It cranked twice, stopped for a second, then started cranking again. (all with the key in the start position.) Started up, chugged a bit, and stalled. I was able to get it going the next time I engaged the starter.

Once she was running, I put it in Drive, and it darn near stalled out again. Taking it down the road during the first 1/4 mile it was chugging. IE it normally idles about 500 RPM and it was dipping to 300 then back to 500 and down again. The automatic trans. was also shifting at a much higher RPM than usual. Taking my foot off the accelerator and she'd drop power and almost stall. (it never did, but felt like it wanted to.) The engine warmed up, and after 1/2 mile it operated normally. The gauge on the dash is showing the alternator is putting out approx. 15 volts when running.


Any thoughts? I've done some research on it and things are pointing to the coolant temp. sensor. (?)

Thanks!

[jimbob200521]

Originally Posted by drglinski

Hi guys.

I've got a non-cub cadet engine related issue on my truck, and I was wondering if someone could help point me in a direction to look/consider before I start throwing parts and $$ at a problem that might not need parts. Here's what I'm going through:

1997 S 10. 4.3 liter engine. 150,800 miles. 2 wd.
Outside temp: just under 20 degrees F
New battery: January 2015
Fuel: 3/4 full tank

I had trouble getting the ole girl going today leaving work. It cranked twice, stopped for a second, then started cranking again. (all with the key in the start position.) Started up, chugged a bit, and stalled. I was able to get it going the next time I engaged the starter.

Once she was running, I put it in Drive, and it darn near stalled out again. Taking it down the road during the first 1/4 mile it was chugging. IE it normally idles about 500 RPM and it was dipping to 300 then back to 500 and down again. The automatic trans. was also shifting at a much higher RPM than usual. Taking my foot off the accelerator and she'd drop power and almost stall. (it never did, but felt like it wanted to.) The engine warmed up, and after 1/2 mile it operated normally. The gauge on the dash is showing the alternator is putting out approx. 15 volts when running.


Any thoughts? I've done some research on it and things are pointing to the coolant temp. sensor. (?)

Thanks!

How cold is it up there? Sounds like moisture in the fuel filter or somewhere in the system could be a potential issue. As for the shifting at higher RPM's, my truck does that from time to time when it's really really cold out and she's still warming up. Just a thought. Try something in your tank to remove moisture and maybe changing your fuel filter. Just my :TowCents: I'm sure others will chime in.

[cubby102]

No check engine light at all? I had a 98 5.7 do the same thing but it was more of a common issue not just went it was real cold ouy. Ended up being my spider injector.... expensive little buggers too

[MWShaw]

Cranking, then not cranking? I'd look at battery connections.

Starting stalling and erratic idle could all be water / ice in the fuel. Possibly weak fuel pump / pressure?

Higher shift points would not concern me, your ECM may be programmed to hold the gear longer. That allows the trans and engine to come up to temp. My GMC is a 2003 with the duramax / allison trans. It shifts that way when cold. It would not surprise me if yours was set up the same way.

[64fleetside]

Check your ground connections. Scan tool would check coolant temp sensor.

[olds45512]

Just burn it, I've never had an S 10 that wasn't a money pit.

[drglinski]

Thanks for the tips and the quick responses guys.

I'm going to go with the batt. connections right now. That's the eas(ier) part. I had thought about the fuel filter, but again, I didn't want to start throwing $$ chasing things. It's been low-high teen temps here for the past two days.

[zippy1]

Originally Posted by olds45512

Just burn it, I've never had an S 10 that wasn't a money pit.

I had a 84 with 200.000 miles on it and a 96 with the 4.3 with 280.000
miles on it... Rebuilt one trans and that was the extent of major repairs.
I know, off topic from OP question. Just stickin' up for the two good half trucks I had

[J-Mech]

Originally Posted by drglinski

1997 S 10. 4.3 liter engine. 150,800 miles. 2 wd.
Outside temp: just under 20 degrees F
New battery: January 2015
Fuel: 3/4 full tank

I had trouble getting the ole girl going today leaving work. It cranked twice, stopped for a second, then started cranking again. (all with the key in the start position.) Started up, chugged a bit, and stalled. I was able to get it going the next time I engaged the starter.

Once she was running, I put it in Drive, and it darn near stalled out again. Taking it down the road during the first 1/4 mile it was chugging. IE it normally idles about 500 RPM and it was dipping to 300 then back to 500 and down again. The automatic trans. was also shifting at a much higher RPM than usual. Taking my foot off the accelerator and she'd drop power and almost stall. (it never did, but felt like it wanted to.) The engine warmed up, and after 1/2 mile it operated normally. The gauge on the dash is showing the alternator is putting out approx. 15 volts when running.


Any thoughts? I've done some research on it and things are pointing to the coolant temp. sensor. (?)

Thanks!

Computer controlled engines are a little different boogers than our old cubs. You can't whip out a little info and get real far with a EFI engine. Too many variables.

GM don't care about voltage like Chrysler's do. Not running anyway. A GM will run until the battery is too dead to restart the motor. Chrysler.... they don't want less than about 11.5V. Once they get under 12 they get "grouchy".

With it stopping cranking... that could be a few things:
Could be a poor connection with the cranking system; battery connection or a weak connection at the starter, or even a poor ground.
Could be a failing starter.
Could be a fuel leak into the intake. Not as likely with the 97 motor though, more common with the aluminum plenum intake 4.3's.

Could it be the temp sensor.... sure. It could think it's -40 instead of 19. It would make it choke a little harder, idle lower and such.... it could.

Could be a sticky or failing IAC motor.

That trans shift issue is not likely a symptom, near as much as a cause/effect.


All in all, what your going to have to likely do is get some live data from the data stream while it's running. Check the fail codes and make a diagnosis. Normally, this would likely take me..... less than 15 minutes to do. I suggest you go to a mechanic and just be up front. Tell them you will pay for a scan and get their diagnosis or opinion. I suggest an independent shop. Don't even bother going to part stores to get the high school kid behind the counter to go pretend like he even begins to have a clue what he is reading. OBD II isn't in "code" like the old OBD I was, but still, if you don't know what a value is supposed to be, it doesn't matter. I used to give quick diagnostics like this to people a lot. I charged $35 to hook it up and that covered 30 min. A lot of the time, I would go ahead and tell them what I would charge to fix it. If it was an easy fix, a lot of the time I would end up just doing it quick. You may be surprised. Not every trip to the shop costs big bucks. Just take it to someone who knows something instead of fishing on an internet site so people will give you random guesses and you deciding to throw suggested parts at it. Sorry, this is a personal rant for me, so I'll wrap it up. It's not a single cylinder old carbureted cub. It's an electronic controlled, fuel injected truck. It isn't as easy to diagnose over the net.

For the record:
Coolant temp sensor is a good bet. But the cranking thing may be a separate issue.

[mickb72]

Hello,as far as running, fuel filter or water in gas. Have you had the intake gaskets replaced? I have a 96 s10 with 130k. Had gaskets leaking leaking water into intake and out. Gaskets were ate up bad. Gas mileage went down when i quit feeding it water. I have a 96 fullsize with a 5.7 also. PS Hey Zippy i had a 84. Problem with it was a coil mount to a rusty exhaust manifold. Would idle no mater where the throttle peddle was and not miss a lick. Needed a ground. I've been on the interstate berm for miles up and down hills at idle before i got that figured out. WTF Mike