I went to go look at a car today, it was an 88 T/A (light 355, t5 in maui blue/silver, so its kinda a rare color too... Bonus!). The car itself needed a little work, but ran decent and is pretty straight. Besides a few little issues here and there, the car felt a little slow to respond to throttle inputs(in neutral, I.E revving the motor), and ran slightly rich.

The engine ran well and had no issue revving up, but there was a delay between pressing the throttle and the engine actually revving. My dad, aka my 3rd gen guru, said he thinks it has a chip that isn't tuned right for the car, and thats whats causing it to run rich and be laggy. He said he thinks it was chipped because when he did his iroc back in the day, upon turning on the car, both fans came on automatically, rather than just the one, the same as this t/a. He did quite a lot to his car, so I believe him, but I'm not sure fixing the tuning will fix the throttle. Maybe it will help with the running rich, but I'm more convinced the throttle lag has to do with maybe a tps or a loose/badly adjusted throttle cable, as readjusting that on my 92 celica fixed my issue.

While I know a bit about these cars due to research and reading, I don't have the experience working on them to be certain, and didn't get a chance to look that in depth while I was inspecting the car. Does anyone have experience with this who knows what might fix it? Thanks!

 

Hesitation and even a slight backfire at throttle tip-in isn't uncommon with a TPI. However, there are several ways to minimize or eliminate this phenomenon.

Start with the basic maintenance:

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Of course, if the PROM has been altered and enrichment parameters are not optimal, that can also affect it. No one can guess whether the PROM is stock or not - You'll have to open the ECM cover and check.

 

If and when I go to check the car out again, I'll have to check these things. As a newb to these cars, how would one check/ adjust the tps voltage? I can assume you would use a voltmeter or similar instrument to check, but adjusting? Thanks for the input!!

 

There are numerous tech articles on this site outlining and detailing various procedures, including TPS setting. Just perform a search and you should get plenty of information.

Here is an index:

https://www.thirdgen.org/technical-articles/

 

Tps should be set to .54v at idle once the minimum idle speed adjustment is made.
https://www.thirdgen.org/tpimod2/

 

Does it have an adjustable FPR? If So, check the fuel pressure. Too rich will cause a laggy throttle response just a too lean will.