94 backfiring/popping

[stratman440]

I took of my cat 3 weeks ago, and the truck has run fine since. A few days ago while doin some donuts, the truck popped and died. It startd back up and I went on my way. Last night I made a highway run for about 30 miles. On the return trip, I took her up to about 80 and held her there. I let off, and when I got back on the gas to keep her at 60, she was popping like crazy. I limped her along for a few miles, it sounded like she was gonna die, and had no power at all. I gave her half throttle, and the problem went away. I drove her to school today, and after a few donuts, she popped and died again. I started her up, and now she was poppin at an idle. I got her to my parking space, and that is where she sits now. Its a 94 4.3 with 196,000 on the original motor. I was thinkin possibly a wire archin, or an egr. I'm not an expert mechanic, so I'm askin you guys on this one. please help

[Austin8214]

sounds like a timing problem for sure. Or maybe just plugs and wires. You should realy be a little easier on you truck if it has that many miles on it.

[J-Ri]

I'm thinking timing chain, if it's not been replaced.

[stratman440]

Thanks guys, I solved the problem last night. I looked at the plugs, and they were all loose. They are 2 months old, so i thoght that was weird. I went to autozone and showed them one, they said that running 94 octane like I do will kill the plugs. They were exploded on the electrode, so i bought and gapped new ones. I put them in and that sloved the problem. I was wondering how all of my plugs could come loose, expecally if I tightened them down. any ideas.

[J-Ri]

How tight did you torque them? 14 ft/lbs is what many people suggest, others say seat it, then turn additional 1/4 turn.

Running higher octane shouldn't do that... In general, don't take car advice from someone standing behind a counter. If they knew what was going on, they'd probably be turning a wrench. But if you don't need higher octane, don't use it, you're only wasting money. Higher octane gas burns slower, which lets you run higher compression without preignition. If you have a stock engine, 87 octane should do. Consult the owners manual to be sure.

Now that you know the problem, I have to ask. Can a 4.3 break the tires lose for donuts?

[Cadillakin'98]

YES IT CAN!!! My '98 has the capability. However, I opt not to do this on a regular basis. As a matter of fact, I've probably done it twicw in the 2 and 1/2 years I've had it. Don't let those V-6's fool you, they got some b@!!$. But they are only that impressive with the regular cabs (less weight of course).

[stratman440]

I hope that wasnt an insult, my 4.3 can waste some 305's and 350's. I have cold air intake (flipped air cleaner and ripped out tubes and boxe), 3" free flowing exhaust. I have 285/75/16's in it, and I left a cloud of smoke thicker than fog at the stop light the other day. You have to power brake it slightly, but the thing pulls damn hard. I beat my friends 91 350 with it. I gotta ask another question, does the bigger tires affect my speedometer reading? Some say yes, some say the computer can read any size tire accurately.

[J-Ri]

That wasn't an insult, I was just curious. I've got an S-10 with the 4.3 in it (yeah, I know it weighs a lot less), and it'll beat most vehicles in a race, it just don't pull much weight.

The bigger tires do affect the spedometer (all the computer sees is the driveshaft RPM), but that small of an increse over stock doesn't change it very much. I went from 235/85/16 stock to 285/75/16 and I believe it was a 6.2% increase in vehicle speed (figured mathmatically, not actual speed), which means when my spedometer says 100, I'm going 106.2.

[Silverado Brethern]

I got spanked in my truck by a zr-2 s10 with a 4.3L in it. his is a 5 speed and when he shifted 1-2 and 2-3 you could see the front end of the truck rasing. I killed him off the line but he passed me goin about 65. im guessin his gear ratio was a lil higher than mine but those 4.3's can shit n git. Im sure they weigh around 1500-2000 lbs less than me, oh yeh and sorry abot not posting to the ppl that wanted to know how much my truck weighs but last week i got a load of sand and i could see the main weight was on 5900 so im guessing with a full tank of gas and all my truck weighs just under 6000lbs. cant beat a zr-2 but killed an f-150 with a 5.4L every time i raced him.

[98SilvyKid]

Well an F-150 is made by Ford so it's understandable...lol, just kidding. I don't really have anything against them.

[stratman440]

Is that figure for the speed difference the same through all of the speeds, or only at 100mph. my truck came stock with 225/75/16's. Also, could those tires be killing my gas mileage. 10 mpg out of a 4.3 aint too good if you know what I mean

[Silverado Brethern]

I would say the age of the engine and the small size of the engine would be to blame and not the tires, honestly for that truck i wouldnt expext much more than that.

[acewelderman]

I know a circle track racer & he uses a 4.3 putting out 600 hp racing against 355 & 406 motors And winning just because he can place weight around the car where the big cars(heavy)cant!And Im not saying it was cheap either.