S-10 Again. No spark....

[clovis]

I have a 95 S-10 with 4.3 throttle body.

177,000 miles, former owner rode it hard and put it away wet.

I thought I had a fuel problem that has been plaguing the truck for a while. I replaced the idle air control valve after thinking this was the reason for the truck flooding and refusing to fire.

I pulled the #1 plug, and was getting weak, orange spark.

I had DW crank on it again, and then got no spark at all!!!!!! I still don't have spark after trying a few times.

The truck will crank and crank, and then crank some more, but no fire, not even a hiccup or cough. I think the truck is eventually flooding.

No codes from the computer.

Questions:

1. Where do I start to diagnose my no spark problem? This motor has a distributor cap.

2. If there is an electrical problem with a car, will it continue to spray gas, and eventually flood if you keep cranking on the engine?

I am off to the parts store to see if they have any ideas.

Thanks in advance!!!!!!!!!!

[Beeman]

Take a screwdriver with a jumper wire to ground and put it close but not touching the coil output terminal. See if you get a good spark there, if it's food and hot you have problems downstream, coil wire dist cap or rotor. If it's very weak you need a coil. If there is no spark at the coil connect a test light to ground and the other end probing the tach connctor or the neg term of the coil. While cranking the engine you should get a pulsating light on the test lamp. If no light check for power at the pos. coil term. If a steady light you have a problem in the dist., either the pickup or the module.

You say the throttle body is spraying gas, yes that is normal and that usually indicates your pickup coil in the dist. is working as that signals the computer to pulse the injectors. I would unplug the injectors while checking for spark or you will flood or hydro lock the motor. You are also diluting the engine oil with gas.

[clovis]

Wow...I learn sumpin' new every day.

I never thought to unplug the injectors.

Thank you for the input on the pick up coil. That was next on my list of parts to change out. It is one of the cheaper on the list.

I know I must sound like a drop dead idiot when it comes to mechanics, but actually I am not quite as dumb as I might sound. It has been many years since I have messed much with electrical problems. I have mechanical abilities, but fall short on testing actual parts in the electrical system.

Thanks so much!!!!!

Keep the thoughts/ideas/input coming!!!!! I can use 'em!!!!!

[Beeman]

To replace the pickup coil you have to remove the dist and disassemble it, usually pickup coils don't fail as the failure used to be broken wires due to the vacum advance flexing them.

I see from the other post you are removing the dist rotor, is there a reason for this? Have you tested anything?

[clovis]

My testing skills are a little to be desired, to say the least. I own a cheap test light, but knowing where/what to use it, I am at a loss. I'm sure it is easier than what I think, but I'm not even sure what/where those wires go, or the parts.

Simply stated, I am learning as I go.

I believe the truck could use a new cap and rotor, so I am starting there, even though I don't think it is the problem. Both show significant wear. A few months ago, the truck had orange spark, but still started easy. It has been getting progressively harder to start until this past week, and then it wouldn't start at all.

Beeman-as a side note, do you think a Delco-Remy cap/rotor for my GM is better quality than the part that Autozone sells?

It is warm here today, but raining. Since it is Sunday, AZ is my only option. It is supposed to turn cold tomorrow, when the other store that sells Delco is open.

Thanks!!!!!

[Beeman]

Delco-Remy is the safe bet but generally the AZ stuff should be decent. I don't know what ignition AZ carries. I have used Advance's ignition with no problems, they used to carry Sorenson which was Standard Motor Products second line. They now carry Borg-Warner which is also Standard's second line. Most all of it is comparable. Standard Motor Products makes excellent ign. stuff and their caps will have brass contacts.

If I was shooting from the hip it sounds like you might have a bad coil. Do you have an OHM meter? If so take readings on the connectors, I'd have to look up values as I can't remember.

[Madsaw]

A 95 S10 will be electronic advance. So there is no vacuum advance in the dist . Your 95 could have either of 2 style of dist caps. The early one with the wires pointing up or the one with the wires out the sides. The one with them out the sides has 2 screws holding the rotor on. The early one is just pressed on. This one will normal seem like it grows on in time.
With your post saying you had a yellow spark would tend to lead me to replace the coil. The spark should be blue white and really crack. Coils do fail.
Bob

[fixer1958]

If the pickup wires were broken he wouldn't be getting an injector pulse (injector spray).
I'd go with a coil or coil wire.
HEI used to blow holes through the rotor in a cold or flooding situation. I haven't seen that in along time.

[clovis]

Well, you all won't believe this.

I replaced the rotor button and distributor cap. I bought Borg Warner from O'Rielly. I would have prefered an AC Delco, but the BW I bought looks like a nice replacement.

I had a heck of a time getting the rotor off. In essence, it shattered into 87 pieces, after working on it for an hour. It wasn't my intention to destroy it, but it was super brittle, and it happened by accident.

I figured the truck could use a cap and rotor, and since the 2 cost $17, I figured it was a safe bet in the process of elimination.

After replacing these two parts, the truck starts on the first hit of the key...just like a new truck. (I have nice strong blue spark too!) Now, if I just had the new, fancy interior and the nice radio like the ones over at the dealership....LOL.

BTW, I unplugged the injectors like you said, Beeman. Thanks for that tip!!!

Thank you for your time and help. I have learned a lot with your help. Since I am not a trained mechanic, I ask a bunch of questions, and try to be judicious with my work.

Thank you for helping me!!!!! I really appreciate it!!!!!!

[Beeman]

Good Deal! That is a good vehicle to work on, pretty basic systems and very reliable. Look at the old cap inside at the center electrode that contacts the rotor. It should be a black blunt shaped part that extends down and contacts the rotor. It is most likely worn or burnt out. Also look inside the cap for carbon tracks which would be the paths the spark was taking instead of going where you want it to go, path of least resistance deal. Rotors also can go bad and allow spark to arc straich down to the dist shaft. Since you broke it you might not be able to see the carbon track. Since you've gone this far how are the spark plugs and the wires? Change the fuel filter, air filter and crankcase breather and call it a tune up.

[Madsaw]

Good job!!
Yeap them 4.3 are great to work on. We have a 1999 Blazer and a 1993 1500 pickup both with 4.3. The 99 is a vortec with the fuel injectors and the spider feeding the cylinders. Man I am glad I have a buddy that was a GM guy for many yrs. The later 4.3 with the flat distributor cap loves to eat the cap to teh tune of once every yr. Almost right to the day to boot.
The truck has a NV 4500 5 speed behind it. Can you say over for that motor. It has deep low first for towing and geared pretty good too for a little 6 banger.
Bob

[clovis]

Thank you again for all of the help. I appreciate it more than you know!!!!!!!

There was a bunch of black soot in the center of the rotor. It seemed like an even coat of soot in the center of the thing. I'll inspect what is left of it in the morning.

I was hoping to compare the new rotor with the old one, and at least see how much longer the metal was on the new part. The old metal strip flew off when it shattered.

The wires and plugs are next in line. The plugs are worn, and not shot, but need replacing anyway. I will most likely hire my friend to change those out...he is extremely meticulous in his work and an awesome mechanic, and extremely reasonable, almost too cheap. Those plugs look like they might be a bear to get to. I don't have a garage, so that is also a factor during cold Indiana winters. I might think different if it were spring here.

What do you recommend for wires? What should I expect to pay?

I will definately go with AC Delco for plugs.

Again, thank you for all you help. I've learned a bunch through this process, and am more familiar with my 4.3 than I have ever been. I am also appreciative that your help has saved me some money.

[clovis]

Oh, also, one more question:

Beeman, in one of your posts a while back, you suggested putting something on the new spark plug ends to help prevent the new plug wire boots from sticking to the plugs.

Was that die electric grease?

Thanks!!!!

[Beeman]

You've got it, dielectric grease inside the boots and on the dist and coil metal terminals and a dab of anti seize on the spark plug threads. I prefer to use Standard Motor Products ign wires or factory wires. I have used Belden,NAPA (which I believe are Belden),and Autolite with little problem. I stick with AC plugs on those too.

[Madsaw]

5 of the 6 plugs on my 99 I got through the wheel wells with a extension. But, the middle on on the drive side is hide behind the steering shaft. What a mother. I did have a spark plug socket I could get wiggled on to it. Then I used a stubby boxed end wrench on the end of the socket. It was real fun due to I had to use my left hand up side down to get around the shaft. Just not fun at all. Also this was dine about 2 weeks ago when it was about 15 to 20 here that day. It just makes you work faster.
Bob

[clovis]

Originally Posted by Madsaw

5 of the 6 plugs on my 99 I got through the wheel wells with a extension. But, the middle on on the drive side is hide behind the steering shaft. What a mother. I did have a spark plug socket I could get wiggled on to it. Then I used a stubby boxed end wrench on the end of the socket. It was real fun due to I had to use my left hand up side down to get around the shaft. Just not fun at all. Also this was dine about 2 weeks ago when it was about 15 to 20 here that day. It just makes you work faster.
Bob

It kind of makes you wonder how many 4.3 or hard-to-access engines really have all 6 splugs changed when a tune up is done, LOL.

I've been to a ton of estate auctions in my life, and it is quite common to see a single, brand new auto spark plug still in a box stored away in a tool chest. I have often wondered if that was a single plug that was too difficult for a home mechanic to access on an engine.

On my truck, I think I'll hire the plugs and wires done. This guy works dirt cheap, has a heated garage, and since we are old friends, it will give me a chance to hang out and visit with him. (FWIW, I always pay him more than he charges...he is extremely good, and undercharges me faaaaaar too much.)

[HermitJohn]

Inaccessable spark plugs are nothing new. Seen some on older cars where manufacturer stuffed big V8 in a car not originally designed for it. But lot more common now. Back three plugs on some front drive V6s can be real pain and have to be replaced totally blind.

It was a tight fit putting big 300 straight six in my Ranger, but its whole lot easier to deal with most stuff than on the little 2.8L V6 that was in there. Starter, distributor, spark plugs, oil filter, carburetor, etc are super easy to get to. Due to length of engine replacing water pump probably require removing radiator. But thats lot better than making everything a total pain to work on like many modern engines.

American manufacturers (other than AMC/Jeep who were smart enough to modernize theirs instead of tossing it) made big mistake discontinuing the straight sixes in favor of the little V6s. Ford for instance dropped their perfectly good 200/250 straight six and then spent huge amounts of money making their miserable little gutless 2.8L V6 into the more acceptable 4.0L version. A 250 straight six or even the 200 with modern head like they had already developed for use in Australian and some South American versions of the engine would have been much better engine for a lot less money. I got a 300 stuffed in my Ranger with no body lift, so they sure could have got a 200/250 in there.

[clovis]

Originally Posted by HermitJohn

Inaccessable spark plugs are nothing new. Seen some on older cars where manufacturer stuffed big V8 in a car not originally designed for it. But lot more common now. Back three plugs on some front drive V6s can be real pain and have to be replaced totally blind.

It was a tight fit putting big 300 straight six in my Ranger, but its whole lot easier to deal with most stuff than on the little 2.8L V6 that was in there. Starter, distributor, spark plugs, oil filter, carburetor, etc are super easy to get to. Due to length of engine replacing water pump probably require removing radiator. But thats lot better than making everything a total pain to work on like many modern engines.

American manufacturers (other than AMC/Jeep who were smart enough to modernize theirs instead of tossing it) made big mistake discontinuing the straight sixes in favor of the little V6s. Ford for instance dropped their perfectly good 200/250 straight six and then spent huge amounts of money making their miserable little gutless 2.8L V6 into the more acceptable 4.0L version. A 250 straight six or even the 200 with modern head like they had already developed for use in Australian and some South American versions of the engine would have been much better engine for a lot less money. I got a 300 stuffed in my Ranger with no body lift, so they sure could have got a 200/250 in there.

John,

You bring up some good points. The I-6 got dropped...but they can be outstanding motors.

I thought GM engineered a new I-6 several years ago as the base motor for the new Trailblazers. I read that they spent $250 million for design, research and tooling. It was said that the engine was so balanced and so quiet that they had to put some sort of gizmo on the car so people couldn't try to restart the car once it was running. I have heard people that own them say that they can't hear or feel the engine running.

FWIW, if I ever got rich and had money to burn, I'd build one of those old Chevy 250's to have big horsepower, just for fun. I've heard that an old I-6 can hold a ton of horsepower if you have the cash to blow on performance parts. Years ago, I once drove an old Pontiac Lemans with the I-6 Sprint, and I would bet that it would easily beat a ton of V-8's on the road.

Clove

Clove

[FL.Boy]

Originally Posted by clovis

John,

You bring up some good points. The I-6 got dropped...but they can be outstanding motors.

I thought GM engineered a new I-6 several years ago as the base motor for the new Trailblazers. I read that they spent $250 million for design, research and tooling. It was said that the engine was so balanced and so quiet that they had to put some sort of gizmo on the car so people couldn't try to restart the car once it was running. I have heard people that own them say that they can't hear or feel the engine running.

FWIW, if I ever got rich and had money to burn, I'd build one of those old Chevy 250's to have big horsepower, just for fun. I've heard that an old I-6 can hold a ton of horsepower if you have the cash to blow on performance parts. Years ago, I once drove an old Pontiac Lemans with the I-6 Sprint, and I would bet that it would easily beat a ton of V-8's on the road.

Clove

Clove

Yes the Trailblazers have I-6

[Madsaw]

I got a buddy that is a big I 6 fan. He is building a 292 chevy up right now. Its running a marine cam with a fancy "lump port" head, 4 barrel manifold and split exhaust. Also this one will end up being feed with a nasty turbo too. Nothing like having a little fun from time to time. I have heard of the ford 300's being made into some monsters. They had a great cross flow head desgin already just needed be cam and better manifolds.
Is the trail blazers a I6 or a I5. I know that engine is a nightmare to work on. There is rumor they are having issues with the valve seats coming loose in them too.
Bob