I have a 97 Prelude SH - It has an H22 that is bored out with je pistons, eagle rods, sleeved, skunk 2 cams, dual valve springs, skunk 2 manifold, skunk 2 throttle body, aem ram air it's converted to OBD 1 and it's tuned on Hondata.

When I hold the throttle lightly it will not give even throttle and jerks around. By this I mean it will give throttle, then nothing then throttle, all while holding the pedal evenly.

What I have tried: sprayed carb cleaner to find vacuum leaks, nothing. replaced and re-calibrated the TPS, made it better but issue came back. Tried a different TB (type R) seemed to fix for a second, came back. Tried a different ECU, issue persisted. I am at a loss as to what to do next, I have made sure the TPS and the Map are NOT mixed up. I also took off the intake and verified that the butterflies on the TB are NOT moving while the revs are going up and down.

 

Datalog? What size injectors?

 

Did you check if your TPS has any dead spots ?

 

Update: plugged it into Hondata last night, no errors and the TPS does not read until the pedal is almost half pushed in (which explains why the issue is only with light throttle).

The injectors are RC 1000cc and the car is tuned on E85.

 

Have you calibrated the TPS in Hondata and checked if it still happens?

Assuming that this did not happen when the car was first tuned, has anything changed on the engine, or has the tune been monkeyed with at all?

 

Nothing has been 'monkeyed' with. I drove it about 200 miles before it started with this. After putting yet another TPS on it and my Skunk 2 throttle body it worked fine for about 20 minutes, Hondata reads the TPS fine when the car is not running, key position on, but when the motor is running it will go from 0% (throttle angle) to 2 or 3, then back to 0% it will also stay at 0 sometimes and blik from red to green (signal to no signal). I am tempted to replace the clip on the wireing harness and see if that will clear it up? Also, is there a way to see the TPS Voltage (all I see is TPS angle) in S300?

 

Sounds like a wiring issue, either an intermittent open, maybe a bad ground. Can I ask how exactly you calibrated it ? I assume you did it correctly, but just want to be sure.

 

Ensured it read .45 V when closed and 4.5 V when open. The thing that gets me is it's only giving the trouble when the engine is running. When key position is on, motor off, the TPS is displaying and giving normal readings.

 

It must be something electrical. Run 3 new wires, or just monitor the power, gnd, and signal wires, see which is dropping

 

Is the connector clipping on ? I've seen an aftermarket TPS that actually didn't click on. I had to ziptie it to hold it on the TPS.

 

So it's been a while but I wanted to update on this INSANE issue I was having.

The reason I could not figure out the TPS issues: my Skunk 2 throttle body actually had a defect inside it that was causing the TPS to lose its proper place. Basically the little nub you have to line up was popping out. So that is why everytime I calibrated it it would start screwing up a few hours later. I put a tiny weld in there and I am hoping it will hold, otherwise new throttle body for me.

The reason why swapping out the throttle body did not work - TPS was ruined from slipping out of its position in the old throttle body - I managed to ruin 3 (from the junk yard) by the time this was through.

I figured all this out, then a new issue - car seemed to be in 'limp mode' would not idle over 4000 - cutting out, et.

At this point I was done and took it to my tuners shop - he found that the person who had put in the S300 had actually wired the VTec to a relay, instead of using a VTec ECU - well the relay blew so the car was trying to run in VTec all the time. Talk about a headache! SO I got a new ECU - had it tuned on Chrome and it pushed 200 on the Dyno, not too bad. I think I am going to boost it over the winter (nothing too big, since I don't want to have to replace the pistons) maybe 8 lbs.... shooting for 300hp.

Oh and 2 days after I got it back from the shop - I broke my CV, never knew what hit it, the thing is destroyed. Wonder if they pushed it a bit too much on the Dyno?

 

Glad you got the TPS issue figured out, that sounds like a fun one to track down, and gotta love when people wire stuff wierd, especially when there are easy ways to do it correctly, with what they are using.

With the axle, my first question is going to be how low is your car, and what kind of angles are the axles sitting at?