Anyone mechanically inclined? S10 Blazer no start...

[Frosty]

We had a high of 0 today, that was at 1 AM. It went downhill from there. When DD left for work (she has a 1990 S10 Blazer), it was -9, then when she was ready to come home it was -11. Her vehicle cranks and sounds like it's trying to start but doesn't. DH went out with jumper cables and starting fluid, but still no start. She also told me that it's really down on power (I think that started a week or so ago). She was going up a hill (this is ND, the hills aren't that steep) and could only get up to 30 mph. I guess it has been idling rough too.

My theory is possible EGR valve problem. I was thinking that maybe moisture in the exhaust caused it to freeze up and it could be partially clogged too? Does anyone have any other ideas? We are thinking of looking at it in the morning when we take her to work, at the least I'll take a paper clip and see if I can pull a code. It's going to be around -21 when we take her in so I don't know how much I'll do then, might wait until it warms up in the afternoon. At 3 PM it's supposed to go up to -1.

Any thoughts are appreciated!

 

[rebelcowboysnb]

Assuming a V6? I took my collage Auto Tech in the 90s working on early to mid 90s GM trucks but I have never had to deal with that kind of cold so hard to say. I really dont think the EGR has anything to do with it. They should run fine with it stuck open or closed.

Without codes I would guess bad O2, bad injector or in bad need of plugs, wires, cap or all 3.

Also remember codes in a 90s GM are not all that accurate. It posts codes because of odd readings. A O2 code may be a fouled plug or bad injector. It could be a bad o2 or mean its running rich or lean. On the other hand a TPS code could show up an the O2 is actually bad. Freds brain in those early ones was not that smart.

 

[rebelcowboysnb]

Thinking more....

It cant be the O2 or TPS. The O2 is not used till warmed up an fred should default back to basic cold settings but still run if ether fail.

It has to be ether ignition issues, fuel issue like the pump or injectors or its a clogged air or fuel filter.

This all assumes the engine has not mechanically failed internally.

 

[rebelcowboysnb]

Ya got my brain going.... lol
If it would not at least start an run on the starting fluid then it is ether the ignition system or internal engine damage.

 

[Frosty]

Sorry, didn't mean to make your brain start going...

Yes, it has a 4.3 V6 (what I fondly refer to as a 3/4 350). This is our first really cold temps of the year, and the vehicle sat for a few days after the warmer temps. I just have to wonder since it drove normal in the morning (though normal for the last week included loss of power) then sat all day where DD works if something got moisture and froze. I was also thinking possible crank shaft sensor.

I wasn't there to hear it last night (decided that it was more important to feed my critters) but apparently it's trying to start (even without the starter fluid) but sounds like only a few cylinders are firing. We just bought it in December (long story but has to do with her blowing up the engine in her Grand Am) and it supposedly had new plugs, wires, and distributer cap before we bought it. The parts that I can see look new. It uses some oil but not nearly as much as it did before we replaced the oil cooler lines (hate those things, I would love to find whoever designed them and bury him/her up to their ankles in the cat box with only their feet sticking out).

Last night while doing a search on line for 'S10 cranks but won't start' there were a few folks that had the problem clear up after they cleaned the EGR. Apparently it causes problems if it's stuck open. There was also a service bulletin on the 95 S10, probably a different EGR set up but it said: Some owners with a VCMX-A Equipped 4.3L Engine may experience Linear EGR valve sticking. This may cause DTC 1406 to be set which may be accompanied by poor driveability condition(s) such as engine surge, knock on moderate acceleration, engine stall, rough idle and/or hard starting.

It may not be the EGR but I guess it won't hurt to pull it and check it. Except my fingers doing that in these temps... It gives me somewhere to start.

 

[rebelcowboysnb]

I think the 95 that they are talking about may be the multiport equipped engine but may be wrong. Most S10s in 1990 had the old carburetor style duel plane intake with a 2 injector throttle body where the carburetor use to be. It also has a distributor that handles firing so it wont have a crank sensor. They are for distributor-less and/or multiport engines for the most part.

Though not all that high tech, the whole system in the 89-93 V truck engines was pretty bomb proof. (2.8 excluded)

Hope you get it figured out before you freeze.

I drive a 84 diesel now an it acts like the fuel is jelling at temps in the 20s. Hard to start unless plugged in an when started the fuel pump cant pull enough fuel to keep if from stalling unless its ran enough to circulate an heat the fuel in the tank.

 

[Ole and Lena]

Was it losing power under damp or frosty conditions? My guess is dist. cap and or plug wires or a bad plug itsself or a combination of the 3. Wouldn't hurt to thoroughly clean the battery terminals also if there is any corrosion present.

I owned a '90 S10 for many years. The only mech issue I had was that the distributer cap was prone to hairline cracks if I drove through a big puddle with a hot engine. After that any wet weather or rapid drop in temp would cause condensation in the cap and the symptoms you describe. This is easy to test for. When it's not starting, take a hair dryer to it until it's warm to the touch. Try to start engine. If it starts, replace cap and rotor, keep the old one in a dry place in your truck in case you need a field expedient repair someday. If not, I'd pull a spark plug and visually check for spark. If you have good spark, pull the other 5 and check for spark or any broken porcelain or severely fouled or eroded electrodes. If you have one or 2 plugs that looks good but aren't sparking, try a new plug and vis. check for spark. If still no, replace plug wires. Check all connections between dist cap and plugs, check dist. rotor for wear or corrosion.

 

[Frosty]

Yes it does have the TBI. I won't slam on the 2.8 though... I used to have a Cavalier Z24 with a 2.8 MFI and I loved that car. I would probably still have it but around 290,000 miles it was rear ended by a Ford truck while at a stop sign waiting for traffic to clear.

I hear you about geling fuel, we have a diesel tractor and have to use additives in the fuel for the winter.

Kicking around ideas with my brother, he is thinking possible clogged cat. I went out this morning armed with a paper clip to see if I could get a code, would you believe the stupid check engine light doesn't work? I have been thinking for a while that I need a code reader, this just gave me an excuse to not put it off any more. So going back out in a few armed with that to see if there are any codes. Accurate or not, it might give me a starting point. If I am really lucky, maybe now that it's up to -4 it will start so I could at least bring it home? At least if I can get it here in the garage I would at least be out of the wind.

Thank you for your information...

 

[Frosty]

The cap. wires, and plugs were supposedly replaced before we got it. Unless they cleaned them up really good, the wires and cap look new. They guy said he was planning to keep it but his wife got a new vehicle. It felt a little under powered when we bought it, but I figure that was because I would be comparing it to my '93 that has a manual transmission and had the engine replaced 4 years ago at 275k.

 

[rebelcowboysnb]

Yes, a clogged cat could cause it. Never would have crossed my mind cause everyone cuts them off an sells them first thing down here.


Ole, spraying WD40 in to the cap fixes moisture issues. Good to keep a can in the truck. Take it from someone who knows wet distributors.