Small idle issue

[H311RA151N]

I have a SRI, H23IM with A6 runners. This is on my 93LX.

When i touch the gas it goes up to about 1800rpm and hangs there for a second then drops. It does this everytime i press on the gas at an idle.

I have the plastic screw thing in the FITV screwed in quite a bit. That fixed my idle high idle issue. I dont think its ran in all the way tho.

EDIT: When the rpms climb it makes a "shhhhhh" sound. Then it hangs there for a second, then "shhh-thump" and it idles back down.

[trinistylez]

Is the shhhh sound you describe almost like a hissing sound? Maybe you have a vacuum leak somewhere?

[curtie94]

Just curious did you happen to bypass your air boost valve, When I did the rpms would hang then drop, like you described.

[H311RA151N]

Just curious did you happen to bypass your air boost valve, When I did the rpms would hang then drop, like you described.

Its hooked up.

[H311RA151N]

Is the shhhh sound you describe almost like a hissing sound? Maybe you have a vacuum leak somewhere?

Its coming from inside the TB/IM. I have checked every vacuum line i can find. I even replaced a few that were suspicious.

[dj_ender]

Its coming from inside the TB/IM. I have checked every vacuum line i can find. I even replaced a few that were suspicious.

Did you do a deep cleaning of the IM before installing? And I would be looking at the IACV as the culprit.

[H311RA151N]

Did you do a deep cleaning of the IM before installing? And I would be looking at the IACV as the culprit.

I cleaned out the EGR ports really good aswell as the inside of the IM. I took everything off and used a pressure washer. I didnt clean the TB tho.

I have 3 or 4 IACVs laying around. I have one off of my old IM that i know is good. Ill try that and see what happens.

[H311RA151N]

I have changed the IACV out and i still have the same problem. I cant drive the car in gear under 1400rpms or it will accelerate without me touching the gas pedal. It will continue to accelerate until it reaches 1800rpms for it to come back down.

I thought i could live with this problem but i cant. I have to drive slow down my drive way and its hard when the cars trying to take off. Then when i push in the clutch to slow down it revs to 1800rpm then back down to idle.

It wont quit once you touch the gas. Ive rode the brake with my foot off the gas trying to make it stop without going to 1800rpm and it wont. It just keeps pulling.

['93CB7Ex]

check how your vacuum lines are routed. when i first did mine, it almost did the same thing. some lines are different on h23 vs f22

[SOHC-FTW]

Check for vaccum leaks.

If all is well look into testing your TPS and make sure it's in spec, it will cause a surge under a load aswell.

[H311RA151N]

check how your vacuum lines are routed. when i first did mine, it almost did the same thing. some lines are different on h23 vs f22

I have no idea if i have the vacuum lines ran correct or not. The DIY i used dosent have any pics and the pics i used for a reference were for peoples other projects like P&P or aftermarket TBs and things along those lines.

I never found a good pic of the way the vacuum lines are ran for the H23 IM swap.

So yeah. You could be right. I guess ill play around with them until it runs right.

[H311RA151N]

Check for vaccum leaks.

If all is well look into testing your TPS and make sure it's in spec, it will cause a surge under a load aswell.

I pretty sure there isnt any vacuum leaks. I have checked that time and time again. Ive tried finding a leak with soap and water and ive tried with carb cleaner.

I have a vacuum gauge on one of the nipples on the IM that were caped off.
It reads -20.3 vacuum at idle.

As far as the TPS i was told when i bought it from a member on here that the only thing i needed to replace was the EGR valve which i did.

I guess ill try a new TPS aswell. At this point i dont care what its costs. I just want it fixed.

[H311RA151N]

I forgot to say that when i turn on my A/C the idle surges.

And thanks for all your help guys.

[SOHC-FTW]

No you don't need to jump the gun and buy one. Just make sure your's is in spec, all's you need is a multimeter (Probe the red wire on the tps wires and just ground the ground to the chassis). It should be .5v at closed throttle and 4.5v at WOT or very very close, if it is not you need to try and adjust it until it's in spec. To back the rivet screws out so you can play with adjustment you just need to make a slot into the rivet heads, but you need to check it where it is now before adjusting if even needed.

You will have to adjust a new one to spec aswell.

[H311RA151N]

No you don't need to jump the gun and buy one. Just make sure your's is in spec, all's you need is a multimeter (Probe the red wire on the tps wires and just ground the ground to the chassis). It should be .5v at closed throttle and 4.5v at WOT or very very close, if it is not you need to try and adjust it until it's in spec. To back the rivet screws out so you can play with adjustment you just need to make a slot into the rivet heads, but you need to check it were it is now before adjusting if even needed.

You will have to adjust a new one to spec aswell.

Alright thats easy enough! That would be so nice if thats the problem. I have to go to a wedding in Jefferson City this weekend but on Monday ill get back on here with the results of the TPS.