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Got money to fix one thing, what is it tho?


david-b
11-02-2006, 11:27 PM
Hey all;
Got some cash and I need to fix something, but I'm not exaclty sure what needs to get fixed. We've talked about this numerous time but it's time to make a decision.

When I replaced the thermostat car ran perfect. It's still running great, but one problem that was there before is still there. When I'm driving and I get off the gas and pop to neutral, the rpms drop down to 1k, then shoot up to 2k and sit there until I get to a slower speed, usually just before I come to a stop. Then, when it does go down to about 1k, it bobs around from 900 - 1200 back and forth like idle surge until I come to a complete stop and stay there for a second. I have an idea on what it is, but please give me your ideas.

crunchymilk55
11-02-2006, 11:36 PM
eh, it's not a big deal. ALOT of cars do that. Has to do with coasting fuel cut and some other random stuff. Not something to worry about.

gthompson97
11-03-2006, 02:36 AM
Have you tested the IAC sensors and shit like that? The monitoring stuff on the intake manifold? If you want to, let me know and I can get you some procedures for testing them. The bobbing between 900-1200 is probably normal, but I don't think it should go down to 1k and then come back up to 2k, that's pretty high. How long has it done it? Since you've had the car, or did you do any mods that it happened afterwards?

david-b
11-03-2006, 10:20 AM
I've had EGR code 0440 I think, bad flow of EGR come up since this started happening. But I want to make sure its that before I spend the $160+ for the valve, you know. When I reset the car, its fine, then it starts happening like 200 miles later.

Mikelb
11-03-2006, 10:29 AM
CEL light comes on? just for that code?

I'd clean the EGR... also check the throttle cables, make sure they're set right and not binding... my RS used to do that... mine was because the IAT was bad, I might suggest replacing that (mine set off the CEL) after I replaced that, it seemed to idle right...

also what year was yours, IIRC some years (before 97 I think) had a recall b/c the dash pad wasn't cut correctly and would hang on the accleerator pedal, causing the car's idle to be higher when letting off the accelerator. I'm not really sure why it dips first, but when mine did, it was the IAT (though as I already said, my CEL was on)...

david-b
11-03-2006, 12:51 PM
I've cleaned the egr before. It works fine when I reset the ECU, then it goes back to what it doing now. CEL doesn't come on all the time. Maybe 1 time every 4 months or so. Pedal isn't being touched by the dash or anything.

david-b
11-06-2006, 10:35 PM
So what is the diagnosis, or is it prognosis on this situation? My gas mileage has taken a shit since it started back up. Went through 1/4 tank of gas in 2 days doing pretty much nothing. Before it started back up, gas was perfect. Now it sucks ass pretty bad. I'm thinking of changing the IAC first but I want to make sure bc I have to buy tires next week and I don't want to spend a lot of something I don't need.

Killa
11-06-2006, 10:55 PM
You know how to test if your IAC bad right ? Go with cheap fix first, like if you get new tire, properly good thing is to get alligiment too. and it will be more expensive, find out what you need first, then go with it.

david-b
11-06-2006, 10:56 PM
Actually I don't know how to test it.

With the tires, I know what I need with that. Alignment I've needed for about 2 years now. lol. It's bad. But thats a different story.

Killa
11-06-2006, 10:59 PM
Actually I don't know how to test it.

With the tires, I know what I need with that. Alignment I've needed for about 2 years now. lol. It's bad. But thats a different story.

I dont know if n/t isc is different from turbo isc or not. let me search a lil, btw few year back I remember you post a topic " fix cold idle surge " something like that, you was saying that you have very bad cold idle surge, then you replace new isc and tbs and it fix your problem, if you still have warranty you can take that isc back and get a replacement, I know i can get 1 year old part back to auto zone and still get full money back, im that cool !!.

david-b
11-06-2006, 11:09 PM
They were used. One of those was causing a problem with cold starts. Thing refused to turn over when it was freezing. That's still fine. Have had no problems starting the car yet this winter. They came off of Travis' car. I think I'm going to get a new IAC and then probably an EGR valve. The thing is, those are expensive. I don't want to buy unless I have to. I may get a new TPS too. Any ideas at all?

Killa
11-06-2006, 11:27 PM
They were used. One of those was causing a problem with cold starts. Thing refused to turn over when it was freezing. That's still fine. Have had no problems starting the car yet this winter. They came off of Travis' car. I think I'm going to get a new IAC and then probably an EGR valve. The thing is, those are expensive. I don't want to buy unless I have to. I may get a new TPS too. Any ideas at all?

How much do u have right now ?

gthompson97
11-07-2006, 12:34 AM
IDLE AIR CONTROL (IAC) MOTOR
Avenger, Sebring & Talon Non-Turbo

Turn ignition off. Disconnect Idle Air Control (IAC) motor connector. Using a DVOM, measure resistance between IAC motor connector terminals No. 1 and 4, then between terminals No. 2 and 3. See Fig. See IDLE AIR CONTROL (IAC) MOTOR RESISTANCE table. If resistance is within specification, IAC motor is okay. If resistance is not within specification, replace IAC motor.


IDLE AIR CONTROL (IAC) MOTOR RESISTANCE

Avenger, Sebring & Talon Non-Turbo - 38-52 Ohms at 58 degrees Farenheit

http://img240.imageshack.us/img240/3462/iackp4.jpg (http://imageshack.us)

david-b
11-08-2006, 11:17 AM
I didn't have time to check the IAC yet. Wouldn't it have a really bad idle though if it was it? My idle rests from 800-850. There's a slight dip or pickup every now and then like to ~900 or ~700, but nothing bad at all.

It turned out the little surges, a part of it was an over tightened throttle cable. It logged on the SAFC as 0.01% which caused some problem when the car was really warm. Fixed that.

But the same problem before still exsists. When driving and I pop her into neutral, the rpms drop to 1k, then go back up to 2k and slowly falls down as im slowing down. It doesn't go back to idle until I come to a complete stop. Wasting gas by the bucket loads too.

Killa
11-08-2006, 11:44 AM
If you cool with people at autopart ( autozone, advant auto part ... ) order a TBS and IAC, then install it, if it fix your problem keep it, if not return it.

david-b
11-08-2006, 12:32 PM
Last time I bought a TPS, and they wouldn't return it if it was taken out of the plastic. They're not supposed to do that. Yeah, I bought one a long time back and returned it because I didn't have the money for it :-(

Mikelb
11-08-2006, 12:58 PM
I bought an IAC and they wouldn't let me take it back, I put it on the car, started it once, and found out it wasn't the problem... took it right back off and put it back in box... had receipt and all (and I shop there all the time, they know me by name), but they wouldn't/couldn't take it back...

Killa
11-09-2006, 08:31 AM
That what I say in the first place, that you must cool with the owner or people in there, they gave me 20% their discount to me, most of the time If I ask. But yes I do understand what you guy mean.

Mikelb
11-09-2006, 08:46 AM
That what I say in the first place, that you must cool with the owner or people in there, they gave me 20% their discount to me, most of the time If I ask. But yes I do understand what you guy mean.

I am cool with all the guys there. I'm in there like every other day. I know them all really well. I get a discount (I work for a carlot that has a commercial account), I can even charge parts to the account and pay later. I've even helped them work on other customers' cars...

Shpyder
11-09-2006, 01:18 PM
When I replaced the thermostat car ran perfect. It's still running great, but one problem that was there before is still there. When I'm driving and I get off the gas and pop to neutral, the rpms drop down to 1k, then shoot up to 2k and sit there until I get to a slower speed, usually just before I come to a stop. Then, when it does go down to about 1k, it bobs around from 900 - 1200 back and forth like idle surge until I come to a complete stop and stay there for a second. I have an idea on what it is, but please give me your ideas.

Not a helpful reply from my side, but my 3000GT does exactly the same thing at the RPMs youve mentioned. I just figured it's old ('93, 155K miles, 5-spd SL), and it hasnt broken down yet (knock on all the wood in the world), so I wasnt really concerned. I would maybe spend the money on another problem.

david-b
11-09-2006, 10:42 PM
Not a helpful reply from my side, but my 3000GT does exactly the same thing at the RPMs youve mentioned. I just figured it's old ('93, 155K miles, 5-spd SL), and it hasnt broken down yet (knock on all the wood in the world), so I wasnt really concerned. I would maybe spend the money on another problem.


See, normally I wouldnt and just move on, but it's something. I know it is. It didn't really do it before and now its bad. Gas mileage is being killed too. And just recently after that thermo change the car ran like it should. RPMS were perfect (kinda scarey). I know somethings not right and I'm not going to rest until I find the problem. Except for now because I'm sleepy. I'm ordering a TPS for rather cheap tm so Ill try that first. I believe mine my be shot anyways. Logger only reads 76% at WOT. Going to try there first, then the IAC.

Mikelb
11-10-2006, 07:17 AM
^ are you sure that your current TPS is properly adjusted?

david-b
11-10-2006, 12:30 PM
^ are you sure that your current TPS is properly adjusted?

It's no adjustable on the 420a. 2 screws go into the holes. No sliders no nothing. Just bolts right in :disappoin

Mikelb
11-10-2006, 12:38 PM
Damn, sry man... did you first check it? (ya know, ohmeter style)

david-b
11-10-2006, 01:07 PM
No, but it's used. Came off a car with like 130k miles on it. Like the cable is set great, TB is set great, but the logger reads 76% WOT and 5% idle. SAFC reads different stuff all the time. And it's shakey on the safc. It's never steady unless at idle

Mikelb
11-10-2006, 01:13 PM
No, but it's used. Came off a car with like 130k miles on it. Like the cable is set great, TB is set great, but the logger reads 76% WOT and 5% idle. SAFC reads different stuff all the time. And it's shakey on the safc. It's never steady unless at idle

Well, I'm hoping that at idle it reads 0%, but have you checked the wires for a short? I know my Talon has a problem (and will even read positive) when the car's idling, that's b/c the clip on the harness is missing and the harness sometimes decides to come off. As soon as I put the harness back on, the idle issues fix themselves.

There's a way to check the voltage on the TPS (with the AFC). I b/l you go to setup and sensor check or something like that... I can't member (my car's been down so long now)...

^Then again, my AFC's crazy and thinks it's reading knock in my Talon.

david-b
11-10-2006, 01:22 PM
IIRC, the voltage was very shakey on it. The clip is tight in there, no movement at all. I actually have problems taking it out when I need to.

Mikelb
11-10-2006, 01:28 PM
hm... well, I wish you luck. Maybe that sensor will fix it. I just didn't want to see you have to spend that kind of money. (I assume you bought a used one, the new ones are overly expensive)

david-b
11-10-2006, 02:00 PM
It's new but I;m getting it for pretty cheap. I still think it may be the egr valve but that's the last thing im going to change cause thats most expensive. Thanks

david-b
11-14-2006, 12:32 AM
Ok, so today I was driving this morning and going to work, I raced a mid 90s BMW. It was a boxy 4-door (stick) with some kid driving it. He kept looking at me all checking out the car and all, just riding side by side. The road turns into an expressway (4-lanes) and when we passed the light, we dropped to 3rd and took off. I went through 3rd all the way up to about 6800rpm, which is the highest the car has been in a long long time. Oh yeah, I beat him by about 5-6 car lengths FYI. Good times right there.

Anyways, after that, the car ran perfect. Like the idle was great. I would pop back to neutral and the rpms would fall and stop where it should be perfect each time. Then later tonight here, it started going back to the way is was, being all jumpy and rpms dropping and then going back up.

So this got me thinking... after bringing the car up to high rpms, WOT and making the car work, it ran perfect then. The only thing that I can think of that would affect something like that would be the EGR valve. Seems like all the exhaust that was flowing out of the car either pushed or closed the EGR valve making it work fine again. Then, after normal driving, it got stuck in the position again. Sound about right? Maybe? Anything?

I ordered a new TPS this morning before I had this race and thoughts, but that's ok anyways. Want a new one on anyways. What do you guys think? Thanks!

Mikelb
11-14-2006, 07:50 AM
Well, the EGR is a possibility. You even said the code came up. I'm gonna guess you'll have to go that route. Less you block it off. I don't guess you can do that b/c of emissions restrictions though.

GL and keep us posted

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