CDHyota

I have a 1990 EX Cab 4x4, seems to not have the power my '92 had which I drove for 12 years. Bought this truck recently and it had sat a lot (3k miles in 10 years). Doesn't pull good up slight hill or when going into 25 mph wind. Have done FI cleaner, fuel pump, CC removed and nothings changed. Tail pipe seems to have plenty of carbon on it. Other than this the truck runs perfectly. Truck has 83k miles.

coryc85

What axle gearing, tire size? Manual or auto?

The cheap and easy things to do would be adjust valves, set idle, set timing, and adjust your TPS.

beyond that, i don't think any FI cleaner in a bottle really works, I'd send them out for real cleaning, then new plugs, wires, cao rotor.

CDHyota

Thanks. 235/75 R15 5 speed on both trucks. I wondered if maybe this new truck had taller gears but I'm not sure. Will look into the other suggestions. Thanks again.

wyoming9

iTrader: (1)

Do a compression test see what your working with.

Some climates rings rust fast in a short time

Marvel Mystery Oil is your friend but all bets are off if it was cranked with rusted rings

CDHyota

Thanks for the suggestions.

Co_94_PU

iTrader: (-1)

New TPS, new timing chain best bang for your buck.. There is some leeway in the throttle angle but it's not ideal to run on the borders of what the ecu expects. Valve timing will make a big difference in what power you see and when.. I'd like to recommend a new VAFM also but unless you find new old stock I don't really trust modern quality control particularly in knock of parts.

kapnd

My 96 t100 lacks grunt on the top end, I have done all the normal tune up stuff with no change.
Found the throttle cable to be pretty stretched out, and the grounding system weak, but only marginal gains after repairing those items.
How do you adjust TPS?

yota tay

From the neutral position turn it clockwise very very slowly with your meter prongs set to ohms on the bottom 2 pins. When the meter deflects tighten screws at that exact spot slowly on each side. Verify with meter tps is in deflection after tight. Then verify that any movement of throttle plate changes the resistance accordingly.

kapnd

Thanks, Tay
This may be a little over my head, didn't realize it was an electronic type of thing. Hopefully one of my kids will be around to help me!
I just hope I'm on the right track. Now I'm reading about MAF and CAT and other electronic thingies that can affect performance, how do you know where to start? I cant afford to just buy new parts in hopes that they will help, if that were the case, I'd just buy a new truck!
Just kidding, I really like the old T 100, and drive it every day for my work, carry lots of tools and materials too, so I'm sure that extra weight has some effect on performance as well, but dammit, its a truck, and should be able to handle truck loads without falling on its face!

Co_94_PU

iTrader: (-1)

its not rocket science, just proto-rocket science..


TPS adjustment:
​​​​​​This is a good practical basic multimeter lesson, you can't hurt anything but your knuckles, you will do fine. It can be frustrating to get the screws tight, it helps to have clipping meter leads and three sets of hands

How to:
There are trouble shooting checklists and flow charts in the service manual. Following these you will very rarely replace anything that doesn't absolutely need it, no need to throw money and parts at an unknown problem. follow the book until you have a better understanding and then you can maybe skip over a step two, but sometimes that will go down the wrong path even for the most experienced person.

Load:
It might not fall on its face but don't be surprised when it wants to crawl on its hands and knees, it's only a four cylinder with around one hundred horsepower after all