Ok so I've had this problem for awhile now but recently it's gotten alot worse. The symptoms are when I'm driving, engine will jerk in any gear when i'm giving it no throttle to about half throttle, and the tach shows fast jerks up and down too when the engine's misfiring, if I push the clutch in, the engine will try to find it's idle anywhere from 1000-3000 rpms. Now about every 5th time I start the car up and only on start up, the CEL will come on and give me code 7 (tps) then all my problems go away, it doesn't jerk anymore and is completly smooth to drive. Also, my spark plugs are running richer than Bill Gates. i've set the tps time and time again from .45-.50V on idle and nothing makes a difference, so I'm not sure why it's giving me a CEL when I'm getting a good reading from the tps. Any help is appreciated!

 

That's the only CEL you get?

 

Yup.

 

What does it do if you try to drive it with the TPS unplugged?

 

I'll try that first thing tomorrow when it's light out. I remember when I first did my swap last year I left it unplugged and it idled at 3K rpms with constant TPS cel. I'll see if it still does that tomorrow. O, it's also making my gas mileage slightly worse. My spark plugs are taking quite a beating from running rich too.

 

just adjust it. if you can get access to any kind of scantool, it would make it very easy. adjust it so it reads .5v closed/4.5v fully open or closest you can get it to 0%/100%

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prelude_h22vtec &raquo;</TD></TR><TR><TD CLASS="quote">just adjust it. if you can get access to any kind of scantool, it would make it very easy. adjust it so it reads .5v closed/4.5v fully open or closest you can get it to 0%/100%</TD></TR></TABLE>

he said he has adjusted it time and time again.

the SAME EXACT thing is happening to me. I am hopefully going to get to th bottom of this today though..

have you tried swapping out another TPS?

 

Nope I got it from Ebay and the guy said it was taken off a MFPI honda which is 1 of 2 tps sensors for our cars that honda makes, it seamed in fine working order. It's so annoying though, today I was driving and it got bad enough where I took it out of gear but the rpms stayed the same, it can't find an idle when it's moving, it's all over the place. It works like a normal tps from what I can tell, I tested the voltage from idel to WOT and it slowly increased normally when I pushed the gas pedal to the floor.

 

sounds like a vacuum leak to me

and I wouldn't be dealing with sketchy tps sensors.....is the throttle body stock?

 

btw if anyone needs a working tps, i have one.

 

Yeah It's a normal stock honda tps sensor... I just bought it off of ebay.

 

whats up?i juz register here because im having problems, i have a 92 prelude with h22a1 automatic swap, for some reason the jerks on idle or when i stay on D4 on a stop, and when cruising it feels like jerking too, we put sfc vtec controller we know we got the wiring correct because i got it here on honda tech , i dont know if its fuel pump or vacuum leak.. the car has no ac.its bothering me when driving. any suggestions will help thanx

 

Huhhh.... *sigh*......

 

Is it an aftermarket T-Body?

 

The tach jumping is still an issue. I've posted this every time you've made a thread.

There are three things that could make that happen:
1) Bad ecu or bad ecu ground
2) Bad ICM or ICM wiring
3) Bad tach

Since the car is cutting out I don't think its the tach.

 

Heh yeah that is funny u've posted the same stuff for each of my posts. Finally got the cutting out problem at high rpms fixed, u were right it was the ecu ground wasn't tightened down and became loose, I didn't notice until i wiggled it because it was still on there. Anyways, made a big discovery today. I unplugged the Tps which somone said to try and I expected that it would idle really high and have even more problems, but to my surpirse it made the engine run better than it ever has. Completly smooth revving up and down with no misfires and idle was perfect everytime about 1100 rpms when moving and 750 rpms when not moving, like it should. Anyone wanna explain why this would happen? It doesn't make sense to me that it would work better with it unplugged if it's giving the correct voltage from idle all the way to WOT. O and it's a stock throttle body. Thanks for the help Mgags and skunked, and everyone else.

 

Maybe the tps wiring is messed, or its the wrong tps....do you have some extra $$ to buy one used on here and try it?

Today did the tach jump still or not?

 

Nope no tach jumping, when it did it was very very small, because of the jerks and since it was in gear it was causing the tach to jump with the car jerking.
Yeah I guess I'll have to check the wiring next, then try a different tps I guess. It's weird, because the tps is giving good readings to the tps, and getting a 5V constand for the other wire. Guess it's going to be an annoying process of elimination. For the mean time, how hard is it ganna be on my engine running without the tps? From what I know it'l run a bit rich, but the o2 sensor corrects the fuel to air ratio after a couple of seconds, so maybe if I just drive slow. Thanks for the help!

 

it will be fine w/o it, like you said, it will just run rich

 

Ok cool, thanks alot!
Now to solve the problem. Guess I'll start by checking all the wires and everything else.

 

hey, i have a 92 prelude with h22a1 swap auto, lastnight i changed the oil on the car, it was like untouchable, well tonight i was going home,on the way i raced a celica gts i guess with exhaust only anyways i won 4 to 5 carlengths. when i was on the stop i put it on neutral then when i put it to D4 it chokes the rpm went to 500 then when i step on the gas it moves slowly but its choking then when u halftrothtle it run again, it happens whenever i make a stop. im clueless with it.last night it was running strong.pls help

 

Since i'm also having the same problem this guy is i'll ask this question here so we can keep all this info in the same thread maybe it'll be FAQ'd later.

I'm trying to test the voltage reading, and my manual seems liek it wants me to take the reading from the TPS plug, but i'm not getting ANY fluctuation in voltage what so ever. where are you guys taking readings from? and I might as well ask what the right settings shoudl be on my miltimeter to get the right reading?
i am using one similar to this:



i don't think i'm as retarded as i'm coming off as being, but i've tried just about everything and can't figure out this damn TPS....

 

thats the wrong setting man, you've got it set to read amps right now....and that doesn't work unless you open the circuit

anyways, move it to the .02 blue setting by the v with a line over it

 

I didn't use the setting the pic shows. i just pulled a pic of a similar multimeter off the internet. I'm pretty sure that's the setting I was using.. you test it at teh plug right? not at the TPS itself?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by shutta &raquo;</TD></TR><TR><TD CLASS="quote">I didn't use the setting the pic shows. i just pulled a pic of a similar multimeter off the internet. I'm pretty sure that's the setting I was using.. you test it at teh plug right? not at the TPS itself?</TD></TR></TABLE>

you test it with the ignition on with the TPS plugged into the harness. I just stripped back and 1/8" of insulation on the hot lead to get a reading. Then adjust the TPS as needed to get the correct voltage reading.