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94-S10 - Dies while driving and other misc. wacky problems

09-20-2010, 02:37 AM
The immediate question is, can a severed plug wire cause an electrical short?

Make & Model info:
94 Chevy S10 V6 4.3 vin Z, 2w, 5 speed manual trans, air-con, with many miles…(too many to recall).

-Has always had a problem with fouling out plugs, wires, cap & rotor.
-Several years ago clutch was replaced (shop for got to put trans oil in, so…)
-...Trans leaks
-Few months back got in car and clock reset when started. Only time.
-Changed water pump because it was leaking. And fan clutch just because it was a good idea.

Immediate trouble
-Gas Mileage dropped in half (thought tank was siphoned but it wasn't) (this is not a Vortex, it is the Throttle body- so I don't know if the CPI is valid in my truck).

-Began to have trouble starting (turning over), starter sounds strong and battery seemed strong enough to kick the starter. This happened about 8 times.

-Recently, truck started to cut out and wanted to die as I was driving. At first I suspected plug wires because they often work themselves off. (they seemed fine at the time I checked).

- On an extremely hot day, drove ~2 miles and truck drove the best it had in weeks. When I came back, it would not start. (no dash check engine lights or error codes) Again, starter sounded strong, no clicking. I started to think that it might be the alternator (because of the previous sputtering and wanting to die as I was driving). I checked the battery cables for corrosion, they were fine. Then I decided to check the plug cables again, I discovered that one was completely severed…..yeah….I thought I found the problem and did a MacGyver and spliced the cable together and crossed my fingers and did a jig. No luck!.

-Even though the battery sounded strong, I decided to I checked the voltage on the dash. It was lower than I would like to see (~9v) but not the end since I was trying to start it so much.

-Plugged in solar charger till husband arrived with 2nd car (no luck).

-Tried charging & jumping it with cables but no luck.

-Brought the battery to the dealer, they said the battery was fine, I told them it was not and made them do a full test. Turns out it was bad, we replaced it with a new one and once it was hooked up it started to immediately drain the new battery. I barely was able to get it started (6th try) and quickly made it home with the sputtering of the bad plug cable.

-(side note, the car that tried jumping the truck, the same thing happened with its clock twice a few days later and never again. Some kind of car virus?).

-I have since replaced the plugs, wires, cap and rotor.

-I had the alternator checked twice and they say it passes. (Regulator is in the alt in this model)

-Checked fuse box but all looked good.

-No, I have not tried tested the starter, it is not in the best of locations to be messing with. Besides, I am not exactly convince that it could be this. But then again....

So, at this time, I am worried that I have a short somewhere because the bat was completely dead before I even made it home. I immediately disconnected it for good measure. The question now is…where should I go from here? I am afraid to hook up the battery if it is just going to drain it the moment I hook it up or even worse, ruin it.

I am not sure if I have a fuse for the battery, but I doubt that would be the issue either.

Thanks in advance for any ideas and support ;~)


j cAT
09-21-2010, 06:15 PM
I have a 94 s10 vin Z 4.3L 4X4 5 SPeed in my vehicle fleet.

this problem may be a plugged cat converter. poor start, poor mpg, dies when driving.

does the engine run with no smoke out the exhaust ? if this burns alot of oil this would foul the plugs badly. use a hotter plug.

the distributor can get damaged from the windshield washer hose leaking, squirting on it. the coil connections need cleaning. use dielectric grease on the plug wire /distributor boots inside the boot.

plug wires need be routed correctly use tyraps/plastic ties to secure plug wires .

if the starter cranks the engine good don't mess with it. this is not an easy thing to mess with ///motor mounts and etc....

disconnect the battery connections and make sure the starter wires and other fastener hardware is all tight/clean with a wire brush the battery/cable connections till clean..

make sure the alternator is charging the battery . use a volt meter should get 14volts..if less than 13volts its not working correctly. make sure the small wire to the back of the alternator is clean and secure.

check the ground connections, if rusted remove and wire brush the metal reinstall.

remove the upstream O2 sensor leave hole open and see if it runs better. if so then the cat converter is plugged most likely or a restricted damaged muffler possibly.

this has a steel fuel tank replace the fuel filter.

the 5 speed manual uses synchromesh manual transmission fluid. do not use other fluids as this is the best correct fluid.

the leaking may be from the shifter gasket on top of the transmission . the shift boot removed this can be sealed.

that will keep you busy for a while !

09-30-2010, 02:37 PM
Wow, thank you j cAT ( for such a through reply, and I want to apologize both for not replying sooner and not making my post clear...I was concentrating on what I have done and neglected to state the real issue....almost every one of the thing you listed were checked before I made the post but the Catalytic Converter, I don't believe it to be the immediate issue but it was sure on my list of possibilities be for I read your post.

With that said, the Real problem is I have a short that is draining the battery and I was originally hoping that the severed spark plug was the issue. You know, the open wire was touching the engine block and was causing some sort of short circuit. At the time I created the post, I had made the listed changes but was afraid to start it after I did all those obvious repairs (plugs, wires, etc...) because I don't want to ruin any of the electronics on board if there is a short.

I also did not want to use my husbands car again to jump it because I was worried that he would end up with problems too, so I got a battery charger and used the "start mode" and it purrrrrrr'd better than it has for years. I restarted it several times with no problem, I left it over night and it started with no problem, I even took it for a few test runs. I thought I fixed it....It seemed like it was the severed wire.

Then on my way out of town on the start of an 8 hour drive, it ran great for about the first hours worth of driving, the thing started to die again and check engine light is now on....I was barely able to make it to Pep Boys and because Ox-sen was on my original list of thing to change (but i didn't because of the price and the fact that it was running great again) I put a new Ox-sen in and when I went to start it, nothing. The battery was drained again. So, while I was there, they again confirmed that the alt & starter were fine, tried to jump with a portable battery (didn't budge), charged my battery and it immediately drained when I hooked it up....So, we were able to push my truck close enough to the outlet and I used the battery charger and I finally got it running....smooth I decided I better get it home to see if I can find this short.

I took the Freeway because it seemed to only be having problems when it was idling (street driving). On the way home it ran like I had the parking brake on (all gears). Total resistance, like I had both my feet on each petal. Also, now the radiator fan was running on high the whole time and the moment I got in my drive way it DIED again....tried to start it because I was in a bad spot....battery was dead I disconnected the bat ( I know why bother) and it is currently sitting there waiting for me to start testing the circuits.

To answer your previous question about if it is smoking while it is having these The plugs, I have seen worse but the needed changing, and I don't burn a lot of oil. Regarding the routing of the plugs, they are fine, funny story on that. The first time I changed them on this truck I didn't and it was some how interfering and it would act like it was not firing...anyways, and the fuel pump was replace once before....this was also one of my listed things to look at as a last resort, but is currently not in the running due to the short. If it was just the dieing issue I would be tied with the converter in next to do. And in regards to the started, it is strong, I have always ruled it out even though everyone keep trying to say it is, it is in a crappy location...avoid till I have to ;~)

Summary of current symptoms.
-Check engine light on (I will try to check the code if it is still there when I jump it again, I don't expect it to be)
-Drives like the brake is on during acceleration.
-Battery drains completely
-Rich fuel (I am worried that a module is not reading right or the ox-sen check engine light needs to be cleared?)

Again, I appreciate the suggestions and any other insights that you have.

j cAT
09-30-2010, 04:03 PM
If you want some help you must get a volt meter and start checking things out.

a bad alternator will drain your new battery. If a diode in the alternator shorts it will suck the battery down and when driving not produce enough power to charge the system/battery.

with low voltage the engine runs poorly plugs get fouled engine stalls.

so next time you post back details on what you found. meter readings of battery voltage engine on/off

plug wires must be carefully routed very easy to melt/short these wires on the exhaust manifold.

remove distributor cap is it clean in there ?
is the ignition coil clean/connections clean secure ?

09-30-2010, 05:18 PM
Thanks, cap, dis, and everything are new...I told my husband the same thing about the alt. Soon as it cools down I will go outside to start checking stuff (at this rate I might have to wait till February).....thanks again and I will def post back in a few days...thanks again for your help.

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