Bucking/jerking down the highway??

[98sierra4x4]

I halve this issue with my truck where it bucks/jerks for a split second usually going down the highway around 55-75 mph. At a steady rpm/speed. The lights don't flicker either when this happens.

So what do you think my issue is?

(Im thinking plugs and wires, fuel filter, tranny?? U joint, rear end, or something along those lines.)

Thanks in advance.


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[df2x4]

I just had this exact same issue. Replaced plugs/wires, distributor cap and rotor and ignition coil and all is well. Also cleaned my MAF and replaced the fuel filter as pressure was around 6lbs low but I'm not sure if these were related to the issue, think it was the ignition tune-up that did the trick.

 

[jasonreichle]

I halve this issue with my truck where it bucks/jerks for a split second usually going down the highway around 55-75 mph. At a steady rpm/speed. The lights don't flicker either when this happens.

So what do you think my issue is?

(Im thinking plugs and wires, fuel filter, tranny?? U joint, rear end, or something along those lines.)

Thanks in advance.


Sent from my iPhone using Tapatalk

hate to tell you this but this happened to me and the next day i lost 2nd and 4th gear... is there any CEL on? misfire? youd be lucky if there is.. either way a tune up wont hurt, fuel filter 10 bucks, ait filter 20, plugs 40, wires 120 (at least mine were) and your gunna get better economy and just run better for under $200, and its cheaper then a $2000 tranny overhaul

 

[jrollings]

I had this problem around 65-70mpgh. I have a thread on the subject. I had no CEL, but did not know my fuel PSI. I had to buy the actron kit to put the TBI adapter inline. I had good fuel pressue at 29-30psi, my timing was good for my 454 at 10*btdc but I adjusted it to the recommend 4*btdc with no change in the problem. I did a ton of research and was finding ppl saying worn distributor, etc...

I decided to pull my distributor only to find my gear was in great shape. I did however exam the whole dizzy while it was out. End up being a crack in the top of the dizzy under the rotor button. I bought a new dizzy, reset the timing and boom...problem fixed.

sry about the rant but just trying to walk you through how I fixed mine.

 

[98sierra4x4]

I just had this exact same issue. Replaced plugs/wires, distributor cap and rotor and ignition coil and all is well. Also cleaned my MAF and replaced the fuel filter as pressure was around 6lbs low but I'm not sure if these were related to the issue, think it was the ignition tune-up that did the trick.

hate to tell you this but this happened to me and the next day i lost 2nd and 4th gear... is there any CEL on? misfire? youd be lucky if there is.. either way a tune up wont hurt, fuel filter 10 bucks, ait filter 20, plugs 40, wires 120 (at least mine were) and your gunna get better economy and just run better for under $200, and its cheaper then a $2000 tranny overhaul

I had this problem around 65-70mpgh. I have a thread on the subject. I had no CEL, but did not know my fuel PSI. I had to buy the actron kit to put the TBI adapter inline. I had good fuel pressue at 29-30psi, my timing was good for my 454 at 10*btdc but I adjusted it to the recommend 4*btdc with no change in the problem. I did a ton of research and was finding ppl saying worn distributor, etc...

I decided to pull my distributor only to find my gear was in great shape. I did however exam the whole dizzy while it was out. End up being a crack in the top of the dizzy under the rotor button. I bought a new dizzy, reset the timing and boom...problem fixed.

sry about the rant but just trying to walk you through how I fixed mine.

Thanks guys for all the advice, I will put a new cap and rotor in, plugs and wires, fuel filter and clean the MAF. I will let you all know how it goes.


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[vic_v8]

I had a similar problem in my 98, I did a full tune up and most of it went away, it was a NV4500 so I wasn't worried it was the trans. Ended up one of my 2 cats was getting clogged up.

 

[98_k1500]

Cam retatrd settings can also do this on the vortec trucks.

 

[98sierra4x4]

Thanks guys for all the advice, im pretty sure I figured it out. Its a broken distributer, it wont hold the cap on tight.


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[98sierra4x4]

Does anyone know where there is a good wright up on replacing a distributer?


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[GMC1994K1500SierraSL]

What engine do you have?


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