desertdawg70

Ok guys, I have about given up. Here is the deal. My 2002 Chevy s10 crew cab, 140,000 miles, "jerks", or thats the best way to describe it, while I am driving, almost exclusively at high speed. It's almost as though is loses complete power , but only for a spilt second. I have replaced the fuel pump last year and the injectors the year before. My mileage is now around 200-225 per tank, which is well below the 300 or so I usually get. I was told that the problem was the spider injector system, so i replaced them 2 years back, and it solved the problem until about 3 months ago. Supposedly the injectors leak some fuel, cause the "jerk". The injector system is about 300 bucks, so I am dreading replacing them again, only to have them start to go out. I have no idea what's wrong, but I do know that my O2 sensors are going off again, and I occasionally get the code that says my gas cap isnt on tight, when it is. Has anyone ran into this "jerking" before? I am wondering if it is the injectors, or if something else is causing the injectors to go bad.
I will be checking back often, and I am taking the truck to have the codes read again tonight.

Thanks, and let me know if you need any other information.

MDTAHOE

What is the condition of the plugs and wires?

desertdawg70

MDTAHOE-
The plugs and wires have about 25,000 miles on them. Also, I should note, that the jerks can be anywhere from 5 minutes apart to 15 minutes apart, and sometimes never.

97RedBull

the tps can also cause a jerk or surge like this under a load and certain rpm but i would say maybe the coil or coil wire? maybe its arching on something? loosing all the spark to the cylinders for that split second.

desertdawg70

Thanks Redbull,

I will check the TPS this afternoon, but how do i check the coil?
Also, I noticed that its getting tougher and tougher to start the truck cold now. 3,4,5 times to get it started. I also noticed while driving home from Columbus last night, while I am going uphill the RPMs will spike sporadically 2-300 RPM, I can hear it in the engine, see it on the tach, but my I can't "feel" my speed picking up. I know its happening, but it might be normal. I have been trying to pay more attention to the truck itself, so i am starting to notice things I normally don't.

MDTAHOE

You may want to look into the fuel pressure

2000sdime

^^^^^^^ yup cuz i think mine throws a code about the fuel pressure and it does the rpm thing you were talkin bout but not as bad

elaw2004

i have the same problem with my 97 Blazer,, anyways ur guys input has helped me alot on deciding to get rid of my headache and trade it in, i did find the Spider Injection System for alot cheaper though, u can get it for 189.00 at a site called JustFuelInjectors.com hope this helps.

babe s-10

Amazing! My 2002 s-10 is doing the same thing (see post 9-13-10). In your experience what should I do next? You say you are getting codes...which ones?

Thanks

Babe s-10

Kash Ybeink Henderson

Changed tps and fuel filter problem solved no more jerking .....had changed spark plugs, wires, coil pack, cleaned throttle body no change runs like a dream now