Throttle body spring

Denunzio36 · Apr 25, 2006

If I were to put a stronger spring on my thropttle body, would this help fix the problem of my RPMs coming down slow? I figure the plate must be staying open for a bit longer than it should...Thanks

wiplash · Apr 25, 2006

I don't think the spring is the problem. It's called a hanging idle and its common on the sn95's. Disassembly and cleaning of the engine's top end may eliminate this. Basically your ecm doesn't like something thats going on.

Denunzio36 · Apr 26, 2006

If I just had the car data logged, shouldn't this have fixed this? An SCT was burnt for my ECU, this should be able to be programmed to manipulate the the computer to run correctly no? I just dropped 400 bones on this chip. The Tech said the chip should learn....Can this problem be fixed? Thanks

94yellowgt · Apr 26, 2006

Mine would still hang alittle even after I had the chip burned. We even adjusted the allen head screw on the throttle body that allows more or less air to the IAC. We got it as low as we could before it would start to surge again, then turned it open about a half a turn and it was fine. I did a Fox Throttle Body conversion and the junk throttle body I have now, does not have the adjustment on it and my idle was hanging really bad, so I just unplugged the IAC and it does not hang at all now. However, I do not like it this way very well, so I will be getting an Accufab soon.

ryclef331 · Apr 26, 2006

Your hanging idle is caused by your Idle Air Control Valve not responding quickly enough. Either is old and worn out, dirty, or just can't keep up. You have an adjustment screw that you can use to play with the idle. In makes it lower, out bring is up. I've seen people unplug their IAC and then open the screw until the car runs. Plug the IAC back in and bam...it works. You can try cleaning out the IAC...its on the side of the throttle body next to the TPS sensor. Its the bigger of the two black components. I would NOT reccomend using the allen key on the side of the throttle body to hold the throttle blade open so the car idles. This is NOT idle...thats part throttle. I've seen it work but I wouldn't do it on my car. The TPS isn't reading idle therefore you're just tricking the system. People say the 94-95 ECU "compensates" for it. If you have a shitty TPS sensor that is reading 2.34V at closed throttle...it isn't going to compensate for that (had one shit on me) so you may wanna look into that as well. I've seen it work but I wouldn't do it on my car. Its a band aid for a bigger problem. I have a H/C/I 331 stroker with 30lb injectors that I was able to make idle like a champ on the stock ECU and STOCK Tune. I had a CEL but it was for the EGR which was deleted. With all your sensors in working order, there is no reason you can't get the thing to settle into an idle. I have a slight surge when my car is cold but once it gets a little bit of heat in the motor, its great.

Denunzio36 · Apr 26, 2006

My only concern is my clutch...If RPMs are hanging while I'm letting my clutch out, I'm putting necessary wear on it. Does this happen to anyone else? Are you guys going through clutches? I can already hear my throw out bearing starting to chatter.

As for the last post...My IAC is brand friggin new...TPS is dead nust at .96 closed, just about 4.0 open....I'll try unplugging the IAC and playing the the throttle screw as stated below..This is buggin the shit out of me

Addermk2 · Apr 26, 2006

my car was doing the same thing until i took my battery out... but every now and then itll still hang a litle high. right around 1700 rpms. but it does it mostly when its wet out..... i still cant figure THAT one out

Lightning Struck · Apr 26, 2006

ryclef331 said:
Your hanging idle is caused by your Idle Air Control Valve not responding quickly enough. Either is old and worn out, dirty, or just can't keep up. You have an adjustment screw that you can use to play with the idle. In makes it lower, out bring is up. I've seen people unplug their IAC and then open the screw until the car runs. Plug the IAC back in and bam...it works. You can try cleaning out the IAC...its on the side of the throttle body next to the TPS sensor. Its the bigger of the two black components. I would NOT reccomend using the allen key on the side of the throttle body to hold the throttle blade open so the car idles. This is NOT idle...thats part throttle. I've seen it work but I wouldn't do it on my car. The TPS isn't reading idle therefore you're just tricking the system. People say the 94-95 ECU "compensates" for it. If you have a shitty TPS sensor that is reading 2.34V at closed throttle...it isn't going to compensate for that (had one shit on me) so you may wanna look into that as well. I've seen it work but I wouldn't do it on my car. Its a band aid for a bigger problem. I have a H/C/I 331 stroker with 30lb injectors that I was able to make idle like a champ on the stock ECU and STOCK Tune. I had a CEL but it was for the EGR which was deleted. With all your sensors in working order, there is no reason you can't get the thing to settle into an idle. I have a slight surge when my car is cold but once it gets a little bit of heat in the motor, its great.

good post :thumb:

ryclef331 · Apr 27, 2006

Our cars also have whats called a "dashpot" function. This is the slight hang in between gears to keep revs up a tad to help match the next gear. The only way to ditch this is either a) unhook the IAC or b) get a chip tuned with out it. You can notice it by throwing your car in neutral and seeing the revs will stay at about 1000 until you come to a dead stop, then they'll drop down.

As for the post about it causing extra wear on your clutch....thats BS. The dashpot is there to keep the wear and tear OFF your clutch by matching the rpms more easily. If you mean when you're down shifting coming to a stop....quit down shifting. Unless you're road racing its pointless. I'd rather change a set of brake pads than a clutch any day of the week. The revs also will have no affect on your throw out bearing unless you ride with your foot on the pedal constantly....

Denunzio36 · Apr 27, 2006

It's not that I'm keeping my foot on the clutch, when I let the clutch out, say from 2nd top 3rd gear...I'll hold it to about 2500, push the clutch in (RPMS coming down slow) come into 3rd letting the clutch out, then it'll drop as soon as I get off the clutch, much harder than it should. How is this not putting unnecessary wear on the clutch? I hear what you're saying about the dashpot, but's it the opposite side of that...Dashpot keeps the RPMS up so they don't dive then have to come back up hard when its gets put into that next gear..Mine stays up high, so that the RPMS go down hard when I go into gear.

And I do notice it stays at 1000 until my car comes to a complete stop..this part doesn't concern me as much as the RPMs coming down slow in between shifts.

ryclef331 · Apr 28, 2006

check your tps sensor. A faulty sensor will give out the wrong voltage and cause a hanging idle. I honestly don't think there is anything wrong with your car. When my idle was hanging, it was b/c of the TPS sending out way to high of a voltage @ closed throttle.

Denunzio36 · Apr 28, 2006

The tech said it was at .96V...If I put it lower, might this fix the problem?

ryclef331 · Apr 29, 2006

no...thats right where it should be. Try playing with the idle screw. If that doesn't help, then clean the IAC. If THAT still doesn't work, you might wanna try a new IAC. I've also seen guys that drill a hole in the throttle blade. Start small obviously and work up till you get it. Careful though...its permanent.

hoss13 · Apr 29, 2006

Here's a possible fix. I'm having the same issue and it's driving me crazy. Going to give this a try:

1. Disconnect the battery

2. Take apart the 10 pin connectors.

3. Get a small nail and slightly crimp the female side of the connectors, this will help tighten the connectons. Do this on the complete assembly.

4. Put dielectric grease on the male side of the connectors
and reassemble.

This is the fix for a stuck/high/surging idle. Example: You pull up in the driveway or to a stop light with the clutch in and the car idles it self up to 2K or 3K rpms and then stays there, then finaly drops down when it wants to. Or, your driving down the road, push the clutch in, and the car stays at whatever rpm you were at when you went to make the shift for more than a sec or two.

The 10 pin connectors are black and white plastic connectors that go between the main wiring harness and the fuel injector harness.

Denunzio36 · Apr 30, 2006

Did this work for you? What is this doing and why might this work? Thanks

fredcruz · May 1, 2006

It all starts at the MAF! Look at the little antennaes on the MAF. If their dirty, spray some throttle body cleaner on them to get that gunk out. Next, go to your Idle Air Temp sensor located a little further down the pipe. Do the same. Next, r emove the throttle body and give it a service. Clean it to look like new with throttle body cleaner. At that time clean all the ports for the IAC and so on. When you clean the butterfly, open it and you can see the gunk where the butterfly screw goes through the entire throttle body. Make sure you clean the rear of the throttle body. Don't be surprised when you see all the gunk from years of stepping on the accelerator!