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Hey guys sorry about my multiple posts but I have another issue with my truck that I am trying to get to the bottom of. Ever since I have had the truck I have had a problem with my tranny slipping out of 3rd gear when I am doing 40-50km an hour. Just recently my truck started to randomly chug and struggle for power in 2nd and 3rd gear. It doesnt happen all the time but the fact that it does happen concerns me. Also my truck doesnt seems to have as much guts as it used to in 2nd gear. Doesnt have any guts unless I rev it over 3000 rpm. Anyone have any suggestions? I havent changed/ checked my tranny fluid since i got the truck. Im hoping to get to that this weekend. Hopefully someone can point me in the right direction and I can take it from there. Thanks. Truck is 1987 4.9 I6
Sounds similar to what my truck was doing, only in MPH. replace the throttle position sensor and have not had another problem with it. Pull the stored codes and post them up and you will get many more answers
Hmmmm..., I've been meaning to replace my throttle position sensor since ive gotten my truck but never gotten around to it. I guess its time to finally do it! I'll be doing that this weekend. As far as pulling the codes go I've tried already with no luck but that was on a day where it was pissing rain outside and I had some nice whiskey waiting inside for me so you can probably guess that I didn't spend too much time on trying to pull the codes. Probably a good idea to pull the codes this weekend too! Thanks for the reply.
Do not replace that TPS without checking for codes AND verifying the output with a meter. You will be wasting time and money without a proper diagnosis.
Thanks for the awesome links. Just a quick questions about pulling codes. I am a little confused about how to initiate the tests. All I have to do is ground the STI {the small single input}? Do i not have to do anything with the other, larger module {self test plug}? I am going to save these two links on my comp and try and pull codes and test the TPS this weekend.
All you need to do is ground the single STI plug if you plan on counting the flashes of the Check Engine Light. If you are using a meter then you need to use the ST-Out and Signal Return on the big plug too. If you use a code reader you plug it into both connectors.
Thanks for clearing that up. I am actually excited to pull the codes. Hopefully they will tell me what is wrong with my truck, or at least point me in the right direction.
So I tried to pull the codes today and no luck. First I tried it by just grounding the STI. No luck. Then I tried using a digital multimeter and also no luck. Had it on the proper settings and no dice. Im thinking I may have just done it wrong. Preferably id like to do it without using the multimeter as I think that just counting blinking light would be easier. My truck was warmed up, all electrical components turned off {stereo, ect...}, and i had the STI grounded to the body on the first try, and the neg lead of the battery on the second try. Both times i waited more than 45 seconds for the engine light to start flashing.