|
Author
|
Topic: Why does it seem all the 5.0's get an idle problem?
|
Mustangfiv0
¯
Member # 2231
|
posted
 
 
I have another problem with my idle, First after driving for awhile, my car would surge then die, then i rep[laced the IAC, and the car ran fine, now when i drive it, and i let it idle, itll start at abought 800 rpm, then it will slowly drop till it gets around 400-500, then it just dies, when i start it back up itll idle and do the same thing, what could be wrong?? thanks ![[Confused]](confused.gif)
--------------------
Hp cost money, How much are you willing to spend???
http://www.geocities.com/supra1on1/mycar.html
Posts: 134 | From: Bay Area | Registered: Dec 2002
| :
|
|
Stimson
_
Member # 51
|
posted
Here are things to check: the MAF, making sure the TPS setting is right with respect to the idle screw setting, having no vacuum leaks, no leaks/cracks between the MAF and throttle body, cleaning the IAB and 10 pin connectors, making sure O2 sensors aren't dead, not having initial timing overly advanced and things along those lines have proven to fix idle surges.
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
u guys r still not giving enough info on these kind of problem. people all say the same thing, and nothing ever works. i checked everything im ean cheacked everything, except my 02 sensors, went to do it today but i couldnt get them off, ill do it tomorrow, i have ran codes like every two weeks nothing has came up, except that i had a code about to lean of left side 02 sensor, so thats why im going to replace them. car idles perfect at start then tends to fall off after a few minutes. let u know how it goes. mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
DropTopFox
drama
Member # 1689
|
posted
This happened to my car when we put on the cold air we unplugged something that was near the throttle body. When we plugged it back in the shit went away and idles like a champ. CHeck all the connections around the throttle body! ![[patriot]](graemlins/patriot.gif)
--------------------
Go out and do something for yourself today everyone, quit depending on others
-Me
http://www.CaliforniaFords.com/cgi-bin/album.pl?album=00001689
Posts: 4003 | From: San Bruno | Registered: Aug 2002
| :
|
|
Mach103
¯
Member # 746
|
posted
i have done that before, i have checked everything stuff like this doesnt always happen, it has to be real simple but i cant figure it out i have heard lots of cars with me more bolt ons then me, and there cars idle perfect. my car has idled great at one time not no more.Mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Stimson
_
Member # 51
|
posted
Of course I'm assuming everything is mechanicly sound with your motor. No bent valves, blown head or intake gaskets, no cracked spark plugs or burnt wires, ect.
Can you honestly say you've checked everything? What is your TPS voltate at idle and at WOT? (engine off of course).
What is your fuel pressure at idle? What about MAF voltage? Did you take out the electronics and made sure no K&N oil is on them? What kind of vacuum are you pulling? What codes from the EEC? What about injector balance test results? I/we can go on and on with basic 5.O trouble shootig here....
Oh yeah, if your EGR is slightly stuck open, it will cause idle and light throttle problems as well.
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
i cant say i have checked everything. i know that my car runs great no blown head gasket and no blown gaskets what so ever.no craked sparked plugs and no craked or burnt spark plug wires.um assuming that my injectors are fine they arent leaking or no sign of them failing.mass air seems to be fine its brand new, slight problem with mass air i had to slice the wires to make the wires longer for the super charger so that can be a problem but i dont think so because it didnt way before that. no oil on the little elctronic thing the mass air checked that. i checked my 10 pin conectors, cleaned pretty well. my tps is at .98 when i checked today, um EGR seems to be working sucks in and out when taking the vacum hose off/on. um i have a msd coil, its hella wobblie, not very secure. o2 sensors dont know if they ever have been changed. um some days car drives well then it has its days, car does have a idle probelm also has another problem when driving at a certain speed tends to be low rpm and if u hit the gas real quick the car hella bogs/shakes, dont know what that is from bad throttle response. sorry so long. help please. Mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Mach103
¯
Member # 746
|
posted
oh im also pulling 10 pounds of vacum at idle and im thinking my fuel pressure is around 35-40 lb of pressure. i had it at 39 when i took the supercharger off. sorry mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
mustangcam302
¯
Member # 2315
|
posted
U may wanna see if ya could swap another EGR on there, or possibly look at the EGR position sensor too. B/C that EGR valve isnt suppose to be workin at idle or WOT only at cruise.
Posts: 163 | From: San Diego CA | Registered: Jan 2003
| :
|
|
Mach103
¯
Member # 746
|
posted
well i mean the EGR looks fine because when at idle if u take the vacum line off the EGR the bladder inside seems to be working sucks in and out. dont know if u cant if its working that way thought u could.mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Stimson
_
Member # 51
|
posted
Back off on the TPS for sure! Aim for low 0.80 volts. Never ever run 0.98ish TPS volts. Thats some old bad 5.O tech right there. I purposely run about 0.75ish volts on my TPS sensor just to piss off the clueless ![[Big Grin]](biggrin.gif)
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
i cant have it that low, because there is no way my car can idle that loew
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
mustangcam302
¯
Member # 2315
|
posted
U can test the EVP:
While lookin at sensor with the convex(curved) portion of the sensor facing towards the right so it looks like the letter "D":
the sensor points look like this:
.
. . The dot on left=EVP SIG
. The dot on right=VREF
The dot on top=SIG RTN
The bottom dot= not used
Test: You are gonna do a KOEO test, disconnect the harness from the EVP sensor, disconnect the vacuum line to EGR, hook vacuum pump up to EGR and increase vacuum...check resistance between EVP SIG and VREF....resistance should be 5500 ohms-100 ohms as vac increases....if not, EGR valve or EVP sensor may be faulty.
Posts: 163 | From: San Diego CA | Registered: Jan 2003
| :
|
|
Stimson
_
Member # 51
|
posted
quote:
Originally posted by stangbanger:
i cant have it that low, because there is no way my car can idle that loew
Why can't you? Tighten the idle screw a bit and lower the TPS. I'm sure you can find a combo that idles. I know what you're talking about though, blower cars are a bit more touchy when it comes to this. Having the TPS so close to 1 volt will cause you to possibly cause the EEC not to go into idle stratagy. Even if you can only get it to 0.88, you're better off than 0.98
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
i dont have a blower on the car anymore, but now the TPS sensor is all the as far as it can turn. and the idle is at about 850-950, i really dont think the car can idle any lower then that, if there is way to get the TPS any lower i would like to know.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Stimson
_
Member # 51
|
posted
Drill/grind the TPS's mounting holes bigger or try a new TPS sensor. They vary a decent amount from one sensor to another.
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
its a brand new TPS that on there right now
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Mach103
¯
Member # 746
|
posted
so u say that i can drill the holes out just a little bit more and set it lower then .98 volts, and have it idle about 900 rpms.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
John91coupe
CAFords OG
Member # 18
|
posted
I have a dumb question. What cam are you running to get only 10" of vacuum at idle? That's about what I get with a pretty agressive cam. I'm sure you checked already but it sounds like you are losing vacuum somewhere.
--------------------
D-2R ProCharged R302 331
1.410 60 ft.
5.784 @ 122.92 1/8
8.953 @ 155.08
MM&FF Feature June 2003
Posts: 1361 | From: Grass Valley, CA | Registered: Sep 2000
| :
|
|
Stimson
_
Member # 51
|
posted
Doh, good point John, I didn't even catch that last night!
stangbanger- You can get the car to idle at any TPS setting at any RPM. If you think 900 RPM is too low of an idle for you at a 0.85 volts TPS setting.... tighten the idle screw a bit to increase the RPM and lower the TPS setting down to 0.85 or so. TPS voltage is measured with respect to the idle screw setting.
Posts: 2373 | Registered: Jun 2000
| :
|
|
Mach103
¯
Member # 746
|
posted
allright went out to the garage today and i drilled out the holes on the TPS sensor, I got the voltage down to .83 volts, didnt change anythig only thing is that, car idles a dream at any start up, but when coming to a stop there go's the surging again, but i noticed that i had a leaky injector the one under the fuel pressure reg. found a puddle of fuel. can that be my problem with the surging, can i buy just one injector, and where from 36lb.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Stimson
_
Member # 51
|
posted
Hey, we're making progress! Is the injector leaking or just the O ring? You can buy new O rings for 5.O injectors from the Ford dealership or NAPA autoparts for sure. I don't know if any other autoparts stores carries them first hand.
When you install the new O rings, put a light coat of motor or tranny oil around them to help them seal and fit snug.
Posts: 2373 | Registered: Jun 2000
| :
|
|
Stimson
_
Member # 51
|
posted
Oh yeah.... my logic for not liking 0.98 volts. I honestly own over half a dozen volt/multi-meters. I can hook 3 of them up to the same source and get 3 readings more than .02 volts apart. I'm sure the EEC's calibration is more off than my meters so setting the TPS voltage so damn close to 1 volt is risking the TPS telling the EEC not to go into idle stratagy mode.
Also, just from trial and error, I've noticed blower cars are more sensative to high TPS settings.
Posts: 2373 | Registered: Jun 2000
| :
|
|
91PONY
Mrs. Valve Events
Member # 206
|
posted
I used to have idle problems w/my 5.0 until we did the idle reset procedure....I have my idle set at 900RPM's and it idles just fine. Here's the article on how to do it from Corral.net:
It seems that many people have trouble with the way their 5.0 Mustang idles. Symptoms are usually a stumbling or rough idle which may be the result of modifications, or any number of other factors that may contribute to the problem. Clogged Emissions Gas Recirculation (EGR) Valves or Idle Air Bypass (IAB) solenoids are often to blame. A bad Throttle Position Sensor (TPS) will cause the engine to "hunt" for a proper idle setting.
If you are experiencing idle problems first check the IAB. If it has large amounts of carbon deposits in it you may need to clean it using regular carburetor cleaner. You will have to remove it to do this, DO NOT clean it while it is on the car! If you have checked to make sure that your EGR, IAB, and TPS are clean and properly set and you are still experiencing problems try the following:
Clear the EEC-IV's idle memory by disconnecting the battery for 20+ minutes.
Disconnect the Idle air bypass solonoid
Reconnect battery
Start engine and set idle speed to desired RPM with stop screw on throttle body (900 rpm works great with E303 or larger cam)
Turn off engine and reconnect the air bypass solenoid
*Optional -- set TPS to 0.90 - 0.95 volts (Do not exceed 1.0 volts MAKE SURE!) Use a digital volt meter!
Start engine and let it idle for 2 minutes with no accessories on.
Turn off engine for two minutes
Start engine again and run for 2 minutes with every accessory turned on.
Turn engine off again.
Your computer should have now re-learned the new idle settings. This procedure assumes that you have a clean IAB valve. If it is carboned up then you may need to remove it and clean it with carburetor cleaner.
~Heather
--------------------
Heather '91 GT
Posts: 1477 | From: Citrus Heights, CA | Registered: Mar 2001
| :
|
|
Mach103
¯
Member # 746
|
posted
allright guys up date, i didnt find one leaky injector so that means i have to pull the upper off to get to it. so if im going through all this trouble im going to take the valve covers and lower intake off to, to replace the gaskets, really thinking about my car is only pulling 9-10 vacum at idle theres a problem there should be higher so hope all this helps. and ill be changing the 02 sensors too while im at it.What kind of GASKET should i use on the lower and the valve covers dont know what GASKETS to use.thanks mario.
--------------------
2007 Ford Mustang GT
1995 Mustang GT Sapphire Blue(SOLD)
2003 Mustang Mach 1 (SOLD)
2006 Chevy Trailblazer SS
Posts: 898 | From: Yuba City | Registered: Jan 2002
| :
|
|
Email this post to someone!
Printer friendly view of this Ford topic
