[Prince95GT]

sweet

[Reed]

Just a couple of questions from me. I dumped codes on my car today and the only thing that came up is a 12 (RPM at idle out of range) during the KOER test. I'd like to try and adjust the idle to 600 RPM as suggested, but where is the screw on the TB? Is it underneath the spring that has the throttle and TV cable attached?

If I follow the checklist, it should (hopefully) cure my idle problem, correct?

[jrichker]

Mine is under the TB on the side nearest the air intake. The screw head faces the back of the car.

There is a very high sucess rate with the Surging Idle checklist. It is easy to do and not expensive since it helps to reduce buying parts you don't need.

[Reed]

Thank you, I didn't have too much time yesterday, so I'll look around today. Excellent list, I'm glad you created it!

[89-notchback]

Hey Guys, I went through the surging idle checklist which helped me fix alot of stuff, Everything checks out good except i have a code for the passenger side O2 sensor. The engine is pretty much stock except for the ford B-cam which was in the car when i bought it, The car idles good around 800 when not in gear, when i put it in gear( i have an AOD) it surges about 200 to 300 RPM. The car smells rich i assume thats from the bad O2, the IAC seems to be working and i replaced the TPS cleaned all the ground wires, also when i first start it it doesn't want to idle and likes to stall till it warms up a little. I'm gonna replace both O2 sensors and go from there, any other ideas of what it might be?, could it be becuase of the B-cam?, any suggestions would greatly be appreciated.

[jrichker]

Replace the bad O2 sensor and go from there.

[Kabuki_notch]

Jrichker if you are still following this thread a got a nasty stalling problem, I have a IAC and a EGR valve coming in tommrow but before I replace them I want to know if you can tell me which code is killing me.

My car is driven mabey 30 miles a week at this point since I dont have time to drive it when I start it when I get home from work it instantly dies, second startup it idles fine. So I can drive it around after about 10-15mins check engine light pops on and whenever I get to a stop sign or light, the car dies, here are the codes I pulled, keeping in mind this car had a new motor put in and I deleted the smog and a/c

54-IAT
67-A/C (deleted)
81-Airpump (deleted)
82-???
85-Canister purge (deleted)
84-EGR solednoid


thanks for any help!

[jrichker]

Code 54 – ACT sensor out of range. Broken or damaged wiring, bad ACT sensor. Note that that if the outside air temp is below 50 degrees F that the test for the ACT can be in error.

Check the resistance of the black/white wire to battery ground. If it is less than 1 ohm, it is good. If it is more than 1 ohm, the black/white wire has bad connections or a broken wire. Always take resistance measurements with the circuit powered off.

Then check the resistance of the ACT sender located in the #5 intake runner on most 5.0 stangs.

ACT & ECT test data:

The ACT & ECT have the same thermistor, so the table values are the same

Pin 7 on the computer - ECT signal in. at 176 degrees F it should be .80 volts

Pin 25 on the computer - ACT signal in. at 50 degrees F it should be 3.5 volts. It is a good number if the ACT is mounted in the inlet airbox. If it is mounted in the lower intake manifold, the voltage readings will be lower because of the heat transfer. Here's the table :

68 degrees F = 3.02 v
86 degrees F = 2.62 v
104 degrees F = 2.16 v
122 degrees F = 1.72 v
140 degrees F = 1.35 v
158 degrees F = 1.04 v
176 degrees F = .80 v
194 degrees F = .61

Ohms measures at the computer with the computer disconnected, or at the sensor with the sensor disconnected.
50 degrees F = 58.75 K ohms
68 degrees F = 37.30 K ohms
86 degrees F = 27.27 K ohms
104 degrees F = 16.15 K ohms
122 degrees F = 10.97 K ohms
140 degrees F = 7.60 K ohms
158 degrees F = 5.37 K ohms
176 degrees F = 3.84 K ohms
194 degrees F = 2.80 K ohms

[Kabuki_notch]

I hope it's not a broken wire that would be a pain, I will try your test first. Thanks!

[Kabuki_notch]

well I replaced the Air intake temp sensor and that didnt do anything the car still after 15mins or driving shuts off at a stop, so I followed that wire to the battery ground and this happened,




I dont know what this is but it was connected to the black/white wire. I broke the stud right off it. What is this where can I get one? it was pretty rusty/grimey so I cleaned the connection and I must have over tightened it, it snapped

also I saw this was unplugged with a black/white wire not sure what this is either it may not be related.

[jrichker]

The broken part is probably the circuit breaker for the power windows. I can't identify the other wire at this time.

[blackfiveoh]

Originally Posted by jrichker

Updated 17-July-2006

Ranchero5.0’s comments on engines with other than stock cams:[INDENT]A little dragon slaying lore here:

99% of the time on a cammed car opening up the divider between the ports on the IAC with a dremel so the motor idles at 1000rpm with the IAC unhooked, the throttle plate shut and the TPS at .98vdc fixes all surge related problems. Found about to do that on my '93 with a very mild cam and good induction it didn't like idling below 900rpm. The IAC can't react quick enough to a lopey cam induced RPM fluctuation so instead of dampening the surge it increases it. Every E cammed car I've ever worked on needed this to keep a stable idle. Similar to Fords idle bypass plate without the cobbled look. Just dremel out a little at a time till it idles around 1k. In my experience the stock puter doesn't like to idle a cammed car down low.

what i did was cut the gasket between them because i didn't like the idea of dremeling and it worked. You could cut alittle away if it doesn't solve it completely.

thanks for the help this was killing me i tried everything on the list and it was this that worked.

my car ran cold, but as soon you warmed it up it would start to fluctuate and they shut off.

I have a 1991 GT and just added Cobra heads with factory roller rockers, cobra intake, e303 cam, 65mm throttle body, and equal lenth headers.

[jrichker]

The idle bypass plate kit would probably done the same thing. I will have to make note of you experience, thanks for the input.

[Nicoleb3x3]

ok...fix a surging idle a long time ago and had a perfect running stang for the summer...

now; the other day to go to the car wash and get an undercarrige high pressure wash...

the surge started while in the car wash at that exact momment...I though maybe a little water maybe caused it and it would go away..but now it seems only about half the time I still have the surge if I'm in park or neutral...not when I'm in drive at a stop.

..not sure if it's related; but I pulled in to a parking spot; I think I was just moving from drive into park and the car surged forward like I steped on the gas! luckily I had my foot on the brake or I was likely going to hit the front bumper. It happend another time too; sora lunged forward when waiting ...I must have been in drive shifting to park again?

[Nicoleb3x3]

ps. I think I hit my tv cable when flushing out my heater core...maybe I also hit my throttle cable?

could my throttle cable or something have gotten wacked to cause this crazyness?

[GTOreturns]

I thought this thread used to be a sticky?

[Black1987Stang]

Originally Posted by Nicoleb3x3

ps. I think I hit my tv cable when flushing out my heater core...maybe I also hit my throttle cable?

could my throttle cable or something have gotten wacked to cause this crazyness?

The cables shouldnt have anything to do it since it cant open up the throttle without you doing it (mechanically wise with the cable) , I vote for something with the Iac, pull codes and see what you got and post the codes here. After the car wash only think I could think of is something with the 02 sensors? Pull the codes and go from there....BTW Nice Stang

[jrichker]

Another vote to pull the codes. The one item under the car that high pressure water could affect is the O2 sensor wiring. I would inspect it very closely after dumping the codes.

[jrichker]

Originally Posted by GTOReturns

I thought this thread used to be a sticky?

It still is - see the "Useful Technical Thread Index" sticky. It is gouped together with all the other neat technical stickies. Daggar had a great idea when he decided to group them all together.

[Nicoleb3x3]

ok thx
I did notice it only surges in park...occasionally..

as far as the IAC is new, and so are the o2 sensors..I was wondering about the VSS..

but why does it only surge in park? It doesn't surge sitting in drive at a stop (ie stop lights i'm fine)

I haven't had a chance to pull the codes

[87_stang]

OK guys, last night I re-cleaned the IAC and MAF sensor and also took my dremel to the IAC and opened them up together a little bit like mentioned toward the beginning of this thread. I went about 1/8" in so a little air could get between the two holes. I then fired it up and it idled great so I went and picked up my cousin and we just cruised town for about 30 minutes just to hit all the stop signes and stop lights that way I could keep an eye out on the idle. SO far it is working great! Thank you very much to everyone who has helped out by throwing out ideas for me and everyone else with this problem.

[WhitePony93]

I've been through this checklist over and over. My car has a hanging idle problem. With the IAC unplugged, it will idle down to around 800 RPM, but ends up around 1100 (at best) after I drive it. Also, any time I'm rolling with the clutch in or in neutral it's closer to 1500-1800 RPM's(IAC unplugged). My computer throws no codes, everything is cleaned and functioning properly (IAC, EGR, O2's, Baro sensor, TPS, MAF,VSS). I even broke down for the first time in 5 years and took my car to a shop and had them give me a diagnostic. They said sensors checked out ok , there was a vacuum leak, beween the head and lower intake on the passenger side. I had already torn it down to the heads just days before. I tore it down again, being extra careful to follow proper torque procedures. It still runs exactly the same, and I can't even think of any more areas that could even cause a vacuum leak. What should I do? I'm out of ideas.

[jrichker]

Did you replace the lower intake gaskets or just re-touque them?

There have been instances where the gaskets have slipped out of place on installation and caused leaks.

My favorite trick that saves time and effort is the stay in place gasket. Be sure that you scrape (don't use a wire brush) all the old gasket material off, then clean all the surfaces with acetone or MEK.

When the surfaces are clean, use weather strip adhesive on the head to manifold surface. Also use the weather strip adhesive on the side of the gasket that mates to the head. When you are done, the head surface and the gasket surface that mate together will have weather strip adhesive on them. Follow the instructions on the tube or can and when it gets tacky, press the gasket down on the head.

Clean the area where the rubber rails mount to the block in front and in the rear with more acetone or MEK and do the same trick with the weather strip adhesive that you did to the heads.

Coat the rubber seals and the gasket area around the water passages with lots of Blue Silicone gasket sealer and put it together. Bingo! no leaks, and no gaskets that shifted out of place.

If you reuse the injectors from your old setup, a repair kit is available from most auto parts stores if needed. Coat the injector body "O" rings with oil before you use them and everything will slide back together. Take the other advice you got here and run with it.

Fuel injector seal kits with 2 O rings and a pintle cap (Borg-Warner P/N 274081) are available at Pep Boys auto parts. Cost is about $2.74 per kit. The following are listed at the Borg-Warner site ( http://www.borg-warner.com ) as being resellers of Borg-Warner parts:

http://www.partsplus.com/ or http://www.autovalue.com/ or http://www.pepboys.com/ or http://www.federatedautoparts.com/

Most of the links above have store locators for find a store in your area.

Use motor oil on the O rings when you re-assemble them & everything will slide into place. The gasoline will wash away any excess oil that gets in the wrong places and it will burn up in the combustion chamber.

[BK_CAULEY]

when i first crank my girlfriends 1989 gt on the first crank it does its normal 12-1400rom start up and when the rpms come down from the start up it dies. try to crank it again and it does fine. we did this like 25 time in a row. we crank it on time drove it around for about 10 minutes shut it off and it did its dying thing again. let me calrify it a little bit. 1st start cranks then dies 2nd start does fine 3rd dies 4th fine agian and it has done it consecutivly and isnt putting out any codes. any idea's?

P.S.- if any body has seen my threads i started i disconnected the battery while the car was still running and it started surging then it just up and quit now i have problem stated above. but hey without careless people where would be?

[WhitePony93]

[QUOTE=jrichker;6741237]Did you replace the lower intake gaskets or just re-touque them?

There have been instances where the gaskets have slipped out of place on installation and caused leaks.

I went with a whole new intake gasket set.I did use some goo to hold the gaskets in place. I rebuilt all 8 injectors because the little "hats" were brittle and 6 of them had pieces chipped off that went through the motor.The o-rings looked like rubber bands that had sat outside for a month in the sun. Even before I took it in, I could never find a leak with a can of carb clean, so I was a bit skeptical of the mechanics verdict. While I had everything off, I took a straight edge to all the mounting surfaces to check for warpage, none. I checked for cracks, couldn't see any. Not to mention I had just done the intake the week before I finally brought it in. Is there any other way to pinpoint a vacuum leak besides listening and spraying carb clean? I don't think I screwed up the install, I mean the symptoms didn't change in the slightest. Thanks for your quick reply!