Fast idle after intake mod

Topic: Fast idle after intake mod (Read 10661 times) previous topic - next topic

Fast idle after intake mod

Reply #15 – February 06, 2014, 06:15:57 PM

Not only that, Even in Fail safe (FMEM) I saw perfect idle in my car when it has happened.

Quote

And just for the record those engines do not have a Screw to set base idle!!

Really? I see one on all the TB's listed in these 2 pics....

Here's how to reset it: http://sbftech.com/index.php/topic,1031.0.html

The screw on the TB -- on a near stock or stock engine -- SHOULD be set in a manner where the throttle body is closed, but not binding or grabbing on the sidewalls. In a bone stock configuration there should be no need to mess with it. Since the OP's is already fakakta, he's gonna have to get it in place again anyhow

Fast idle after intake mod

Reply #16 – February 06, 2014, 07:21:33 PM

REALLY by now you should know that that is a MIN idle screw not a base idle screw. There is a big difference from a base idle and MIN idle screw.Clearly i have mentioned this 20,times or more posting on this site. I did a a thread on this a few years back. Basically no modern EFI engine controls base idle with a set screw!!!!! Why do you think you have IAC Step counts. And i am if correct in saying Fail safe does not control IDLE speed to any great lengths in an OBD1 Engine management system> By the way the link you posted is not totally correct to set base idle. FORD has the correct parameters ans the ones you posted in fact has wrong info!!!

Also if you in fact do not have a good IAC and i find bad ones all the time you are CHASING BALLOONS. Also the diameter of the throttle plate hole and bypass screw on some TB units also has to be adjusted. I also posted a lengthily procedure to tune the IAC MOTOR!! Throttle plate hole is also critical as it also bypassed air past the throttle plate.

Fast idle after intake mod

Reply #17 – February 06, 2014, 07:43:06 PM

Plain and simple. If the IAC is disconnected. ELECTRICAL PLUG. And the throttle plate is in fact closed and you can not lower the idle so the engine actually stalls the engine is getting AIR SOMEWHERE ELSE. PLAIN AND SIMPLE AN ENGINE WILL NOT RUN WITHOUT AIR!!!

Fast idle after intake mod

Reply #18 – February 06, 2014, 07:44:43 PM

Quote from: thunderjet302;428494

Jebus I just saw that. The completely stock standard 5.0 in my Thunderbird would hit 60mph in about 8.5 seconds or less after a swap to 3.73 gears.

If I had an 8.5 0-60 with my SO engine, I would probably be satisfied (at least for a while lol).

So here's an update, with the car cold, I started it up the idle went to 1100 and then back down to 700 where it should be. I drive it around the block, and then put it in neutral or park and I'm at 1100 idle again. I sprayed around the intake gasket with carb cleaner and all around the IAC and everywhere else I could find had something to do with vacuum. Nothing. In my motorcycle days, I used a propane torch so I tried that everywhere -- nothing.

So then I changed the TPS out with the original TPS from by SO TB. I think it's idling about 1000 now. So maybe it is a matter of adjusting the TPS? Articles I've read said there is no adjustment or that you have to make the screw hole oval to make it twistable. Any comments on that?

Lastly, someone suggested I measure vacuum. Where should I plug the gauge into?

Sorry for these dumb questions -- it's a bit of a learning curve.

Fast idle after intake mod

Reply #19 – February 06, 2014, 07:55:27 PM

First off the 5.0 does not have an adjustable TPS as far as i can remember. The 2.3 does So messing with MIN idle screw is how you adjust it other than removing the sleeves from THE TPS and adjusting it lower than 1.1 VOLTS. The TPS voltage is not critical as long as it is below or @1.1 Volts. To many people set these sensors like a nuclear watch. It does not have to be close by any means. .5-1.1V is fine

Note when i CAM UP the little ford motors i have a special procedure to bring in all the settings so it can be tuned properly. Remember It is always best to use a brand new IAC along with a brand new TPS Set properly. Fords do hunt to some extent so s little hunt is normal!!

Changing the TPS sensors is BAD as FOD actually lists 6 different ones for different tunes. So what is the voltage reading at closed throttle and which TPS are you using. That is part number.

Fast idle after intake mod

Reply #20 – February 06, 2014, 07:59:54 PM

That's 1k rpm according to what? Just curious what instrumentation you're taking that from. My digital tach is tough because 800 rpm free idle looks like 1000 and 800 rpm free idle is pretty good. In gear I was getting about 675, which is just a fuzz high, but it was the best I could do. My loaded idle on my digital tach looked like 800. Just saying, can you trust your instrumentation? Are you using an buttstuffog, an add-on, a timing light with a tach display, a SUN scope etc.

Fast idle after intake mod

Reply #21 – February 06, 2014, 08:01:55 PM

Quote from: marianadeeps;428518

Sorry for these dumb questions -- it's a bit of a learning curve.

They're not dumb until you start asking them twice.

Fast idle after intake mod

Reply #22 – February 06, 2014, 08:32:40 PM

Quote from: TOM Renzo;428516

REALLY by now you should know that that is a MIN idle screw not a base idle screw. There is a big difference from a base idle and MIN idle screw.Clearly i have mentioned this 20,times or more posting on this site. I did a a thread on this a few years back. Basically no modern EFI engine controls base idle with a set screw!!!!! Why do you think you have IAC Step counts. And i am if correct in saying Fail safe does not control IDLE speed to any great lengths in an OBD1 Engine management system> By the way the link you posted is not totally correct to set base idle. FORD has the correct parameters ans the ones you posted in fact has wrong info!!!

I wouldn't know what you posted a few years ago to be honest. Part of the reason I usually disregard your posts is due to the tone of them which this one oozes with. That and every time you throw a fit you delete all your posts. You're stating Ford has the correct parameters? I can guess then you know what those are.

Until I see them I'll go with what came from a guy who helped me with 2 issues on these cars NOBODY else even came close to getting right.
Rather than argue, I'll just let you handle everything.....

You would agree that the OP's TB screw needs some adjustment, no?

Fast idle after intake mod

Reply #23 – February 06, 2014, 08:34:08 PM

Quote from: TOM Renzo;428519

First off the 5.0 does not have an adjustable TPS as far as i can remember. The 2.3 does So messing with MIN idle screw is how you adjust it other than removing the sleeves from THE TPS and adjusting it lower than 1.1 VOLTS. The TPS voltage is not critical as long as it is below or @1.1 Volts. To many people set these sensors like a nuclear watch. It does not have to be close by any means. .5-1.1V is fine

Note when i CAM UP the little ford motors i have a special procedure to bring in all the settings so it can be tuned properly. Remember It is always best to use a brand new IAC along with a brand new TPS Set properly. Fords do hunt to some extent so s little hunt is normal!!

Changing the TPS sensors is BAD as FOD actually lists 6 different ones for different tunes. So what is the voltage reading at closed throttle and which TPS are you using. That is part number.

Ok, I'll check tomorrow afternoon unless is pouring down rain (which it probably will be). I'm measuring the RPM on the digital stock dash but I also remember what idle sounded like before I made the swap and this is definitely faster. Strange that the IAC would bring me down to 700 after a cold start but can't keep it down when warm. Does that mean my vacuum leak (if I have one) gets worse as the metal in my engine expands?

Fast idle after intake mod

Reply #24 – February 06, 2014, 08:47:59 PM

Get a more precise tach for setting your minimum idle. Seriously, that tach in the digital cluster should NOT be taken as a proper indicator of engine speed, especially when setting min idle. I still think you need to verify the EGR plate gasket, Just because you didn't disturb it, doesn't mean it's right. Have you verified all the vacuum ports under the upper intake? The PCV? You base timing is going to affect your idle as well, so make sure you start with that at 10 btdc. When you can verify that there are no vac or EGR leaks, the timing is right, the TPS is between .5 and 1.0v at closed throttle (the closer to .5v at this point the better, since you'll be adjusting the idle screw soon which will adjust UP the TPS voltage), then you can move on to setting the screw (whatever it's called) I don't know what your target points are on a California emission car, but mine is 650 loaded idle (in gear) or 900-950 free idle, per the VECI label on the fan shroud. (pro-tip: spraying the gasket, hose and seal locations with carb cleaner will reveal vacuum leaks by flaring the engine speed up when you spray near the leak site.)

Fast idle after intake mod

Reply #25 – February 06, 2014, 09:19:53 PM

Quote from: marianadeeps;428487

You're saying you think the ECU is stuck in fail safe and it needs to be reset/rebooted somehow? Is this something I can do (capture the codes) or do I need to find some piece of equipment? sorry I'm new to all of this.

just need a paper clip , thats it,, scroll down to my diy link or buzz me if you cant figure it out.

Fast idle after intake mod

Reply #26 – February 06, 2014, 09:36:15 PM

another thing,

stick a vac line on the egr vac port,,,
suck on it and see if it holds your tongue to it,, if not, the plastic diaphram in the egr is blown.

my gut feeling is your correct in that its idle is high... just hope also your intake isnt cracked somewhere odd thats all.
im surprised that a common point wasnt leaking,,, thats not a good sign but not bad either,, it just makes it more of a guessing game.

the IAC is a little deal that lets air sweep around the *CLOSED* throttle plate.
take a peed up in the trottle body and you will see a 1/2'' or so hole on the inside right.
now open up the throttle plate and you will reveal another 1/2'' or so hole just forward.
the iac simply lets air swing around the closed throttle plate during warm up.

As for setting the TPS, you can use a round file to make the mounting holes oval in shape... then dial in the less than or 1volt setting.

if you installed all the old stuff ontop of your bare naked intake,, then i have no clue what it could be other than a cracked vac line you just havent found yet or a cracked intake or hosed gasket.

take your time to also check the black line that travels over to the passanger side along with the white one. These are tiny lines and wouldnt really cause a huge idle increase... but an increase will be shown.

also,, just for the heck of it,, did you forget to connect the vac line on the front of the intake? the vac line that travels down to the carbon canister emissionis solenoid?

now that line is large enough to cause this issue.... you know the one im talking about,, it exits out the front and along the underside of the distributor and down to the forward passanger side of the engine bay,, and goes into the vac canister....

let us know

Fast idle after intake mod

Reply #27 – February 06, 2014, 09:44:25 PM

Quote from: TheFoeYouKnow;428520

That's 1k rpm according to what? Just curious what instrumentation you're taking that from. My digital tach is tough because 800 rpm free idle looks like 1000 and 800 rpm free idle is pretty good. In gear I was getting about 675, which is just a fuzz high, but it was the best I could do. My loaded idle on my digital tach looked like 800. Just saying, can you trust your instrumentation? Are you using an buttstuffog, an add-on, a timing light with a tach display, a SUN scope etc.

I forgot about the factory digital tach being off. The one in my Thunderbird is between 250-300rom off at idle. At hot idle in park my Thunderbird idles at 750rpm. On the factory digital tach it looks like 800-1000rpm. In drive hot it idles at 675rpm. On the factory tach that looks like 800-1000rpm (5 bars lit up). I use an old sunpro tach/dwell meter to set the base idle.

Fast idle after intake mod

Reply #28 – February 06, 2014, 09:47:04 PM

i wish i had never thrown my old dwell meter away,, it was buttstuffog.. i thought it was only good for carbs and such.
had adaptors for checking and setting points and such,, to be honest i didnt know how to use the darn thing... now i think i could figure it out and make it useful for something.

Fast idle after intake mod

Reply #29 – February 06, 2014, 09:48:32 PM

Quote from: marianadeeps;428518

If I had an 8.5 0-60 with my SO engine, I would probably be satisfied (at least for a while lol).

So here's an update, with the car cold, I started it up the idle went to 1100 and then back down to 700 where it should be. I drive it around the block, and then put it in neutral or park and I'm at 1100 idle again. I sprayed around the intake gasket with carb cleaner and all around the IAC and everywhere else I could find had something to do with vacuum. Nothing. In my motorcycle days, I used a propane torch so I tried that everywhere -- nothing.

So then I changed the TPS out with the original TPS from by SO TB. I think it's idling about 1000 now. So maybe it is a matter of adjusting the TPS? Articles I've read said there is no adjustment or that you have to make the screw hole oval to make it twistable. Any comments on that?

Lastly, someone suggested I measure vacuum. Where should I plug the gauge into?

Sorry for these dumb questions -- it's a bit of a learning curve.

You can hook a vacuum gauge to any vacuum source after the throttle body. I usually hook it up inline with the vacuum port for the fuel pressure regulator however any vacuum port on the intake manifold will do.

The TPS should be happy with any reading between .60-.99 volts throttle closed. I think the one on my Thunderbird is around .78V or so.