Have you ever thought about running a motec or mega squirt? I have had real good luck with mega squirt on my supra.
IMHO it might be easier to modify the engine to use an IAC valve and run the 7730 ecm. So far the sail-on has bothered me enough to want to rewire the motor.
[This message has been edited by Mickey_Moose (edited 03-02-2009).]
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03:58 PM
jscott1 Member
Posts: 21676 From: Houston, TX , USA Registered: Dec 2001
You can follow this procedure till the cows have all come home and have all died from old age and it still does not really solve the problem in a manual car. There has even been a tech bulletin released from GM about the problem (setting the base idle lower), but again this does not solve the problem in a manual car - you can reduce it somewhat, but it nevers really goes away.
That has been my experience. I must have done that procedure a half dozen times. Then I encountered a few problems along the way like my TPS is not really adjustable for some reason. Must be a cheap Chinese knockoff or something. And the full procedure calls for the car to idle in park for a certain period of time...well my car is hardwired to be in drive at all times. That can't help, so I was going to add a "park" switch.
The last resort is to trick the car into thinking it's going less than 5 mph when it's really going less than say 20 mph or anytime the clutch is depressed or (if I'm ambitious enough to create a neutral switch) in neutral.
Well went to a few junk yards today a found my 3 pin socket for the temp guage and I also found a perfect 1992 ZR1 with water damage. If anyone is looking for a complete motor they are willing to sell it cheap with everything.
The 4.9 has an Idle Speed Control (ISC) motorized device that attempts to predict the throttle position such that when you lift off the pedal the throttle doesn't slam shut. It also is what raises the throttle when you start the car to improve cold starts.
Unfortunately, it's prone to malfunction in such a way that when you lift off the pedal the throttle doesn't want return to idle and the car doesn't want to slow down, hence the effect "sail on". The effect ranges from annoying to dangerous if you are not expecting it. Below 5 mph the ECM seems to override the ISC and return the car to base idle no matter what.
Stock 4.9s seem to be prone for this effect and it's more noticeable with a manual transmission.
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01:24 AM
jscott1 Member
Posts: 21676 From: Houston, TX , USA Registered: Dec 2001
I am going to ask lots of questions. I have done lots of searching. I mean hours worth! My wife isnt happy. I am not getting any sleep LOL. As you can see from my post times I have been up all night "AGAIN" searching isnt easy. You search and come with 1000's of results and most of the time it has nothing to do with what you are looking for. So I keep this to one thread.
Jscott thank for all your help. Let me ask you this, Has anyone installed a 90's vette dash into a fiero like this one?
Originally posted by TEXASGT: How do I wire up the temp guage? I looked at it tonight but I just dont see what I am looking for nor does that other topic really go into detail
First take a multimeter and check for continuity between the pins on new temperature sensor - Pin A to Pin B then Pin to Pin C then Pin B to Pin C.
The two pins with continuity between them are for the PCM temperature sensor. These two pins need to be hooked to the two wires that are now going to your Cadillac temperature sensor.
The third pin should have continuity between it and the body of the temperature sensor. This is the sending unit for the temperature gauge in the dash. It needs to be connected to pin C2 of the C500 connector. See my previous post for location and instructions for separating the C500 connector so you can identify the pins. There's probably a wire connected to C2-C500. You need to find the end of that wire so you can connect to it or cut it off and splice on a new wire to route to the third pin of the temperature sensor connector
[This message has been edited by sanderson (edited 03-03-2009).]
Some other things that are missing that I need to start looking for. I am missing the vent plate or strut tower mount point. The thing the vent plate mounts to.
[This message has been edited by TEXASGT (edited 03-03-2009).]
Pacethis was in the process of installing a C5 Corvette dash,
but used the 4th gen Camaro gauges instead.
The C5 gauges would require some sophisticated computer trickery to get them to work in a Fiero. I don't believe anyone has done that yet, and I only know two or three people on this forum smart enough to even try, (I'm not one of them)
He ended up selling the car to member War Hammer. Haven't seen much about the car or if the swap was completed.
Most of the images of the swap have been lost unless folks saved them locally to their own harddrive and can re-post.
I dont see why it would be so hard to wire up the megasquirt. I have read other forums where they ran the factory gauges off that system. Maybe it was the motec bu I am really sure it was the megasquirt...
As a matter of fact I have use one of these. I am really thinking installing a ZR1 dash and molding this inthe the factory cluster. Would not be real hard. Even the 1990 prototype could almost be made to fit this.
It's hard to say from the pictures what these connectors go to although the first one is in the location where the MAP sensor would be with valves covers in stock position (oil fill on front cover). You really need to put a scan tool on it and see what's not working. Is your Service Engine Soon (SES) light on? If it's not, I suspect that it is not wired up or the bulb got pulled. With that many things not plugged in it has got to be throwing some codes.
So you're a supra guy too huh? I got a few of those lying around . Do you do all your own work? If you still got one, pm me and ill give you directions up to my shop.
Btw, as a supra guy, you should know SupraForums is full of assholes. SupraMania ftw.
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09:18 AM
BustedRide Member
Posts: 247 From: Kingwood, TX Registered: Jan 2008
Well after spending 6 hours of tracing wires I dont think the OBD harness is hooked up right. I cant even get the ses light to flash a 12 at me!!!
FYI, the Caddy PCM will not flash a code 12 when A/B of the ALDL are jumpered. Nor will it flash out other codes. The only way to check for codes is with a scan tool
[This message has been edited by sanderson (edited 03-05-2009).]
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09:31 AM
Mickey_Moose Member
Posts: 7549 From: Edmonton, AB, Canada Registered: May 2001
Originally posted by sanderson: FYI, the Caddy PCM will not flash a code 12 when A/B of the ALDL are jumpered. Nor will it flash out other codes. The only way to check for codes is with a scan tool
This is correct - the only way to see codes without a scanner is by using the BCM.
I would not worry about some of the wires - to me it's looks like this was a bought harness and as such may contain all the wires for all possible engine combinations. The only way to know for sure is to meter out the connectors and find out which pin they go to on the ECM.
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10:25 AM
sanderson Member
Posts: 2203 From: corpus christi, texas, usa Registered: Sep 2001
Some other things that are missing that I need to start looking for. I am missing the vent plate or strut tower mount point. The thing the vent plate mounts to.
This is a junkyard item. If you can't locate one in Houston, I'd suggest trying to e-mail Rob White the president of Alamo Area Fiero owners. He goes by AAFO here on Pennocks. He has ~25 parts cars on his back 40.
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11:37 AM
sanderson Member
Posts: 2203 From: corpus christi, texas, usa Registered: Sep 2001
Here is the biggest problem to overcome is the idler pully. Its custom made, I think... Its spun to the right and the bely doesnt line up.
It looks like the previous owner kept the Caddy Tensioner and then added an idler pulley on a kinda flimsy bracket in place of the power steering pump. I've not seem this before. The Caddy tensioner is integral with the power steering pump but maybe there is a way to saw off the power steering pump.
Originally posted by sanderson: It looks like the previous owner kept the Caddy Tensioner and then added an idler pulley on a kinda flimsy bracket in place of the power steering pump. I've not seem this before. The Caddy tensioner is integral with the power steering pump but maybe there is a way to saw off the power steering pump.
Hmmm, that looks like a Camaro tensioner to me, the Caddy one would never fit and be able to close the decklid. Here is the stock tensioner modified to work without the power steering pump, you can see it sits way too high (higher than the alternator) - from very early in my original swap:
[This message has been edited by Mickey_Moose (edited 03-05-2009).]
Now that Mickey Moose's picture has refreshed my memory, I agree that you already have a Camaro tensioner. The easiest way to solve your problem is to move the idler pulley to the forward most hole in the water pump. See the link to the Camaro tensioer system I posted earlier. IIRC I had to grind off the lip on the water pump. I also had to add some washers to space out the idler pulley to get it to align with the other pulleys. I did this by laying a straight edge across the alternator pulley and the idler pully at the same time. The straight edge needs to contact each pulley at two points with minimal gap between the straight edge and both sides of the pulley.
The size belt required will depend on the how the Camaro tensioner was mounted and the size of the idler pulley. I'm using a 79" belt.
FieroReinke (Chris Reinke) seemed to be amenable to giving you some help. He's a mechanical engineer. I'd suggest contacting him if you need help.
Should I get rid of the home made one? if you look at the picture right above the covette dash onthis page you will see the home made one. Not the camaro pully? Should I just get rid of it. As you can see in the pic it is bent and not fixable.
[This message has been edited by TEXASGT (edited 03-06-2009).]
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12:51 PM
sanderson Member
Posts: 2203 From: corpus christi, texas, usa Registered: Sep 2001
Should I get rid of the home made one? if you look at the picture right above the covette dash onthis page you will see the home made one. Not the camaro pully? Should I just get rid of it. As you can see in the pic it is bent and not fixable.
Yes, You should ditch the bent homemade bracket. If you mount the idler in the water pump hole, no bracket is required just some spacers (washers) to get the right pulley alignment. The pulleys that most people use are Dayco 89015 ( NAPA 38008) or Dayco 89009. Dayco 89015 is 70mm and Dayco 89009 is 76mm. But your exisitng pulley may work fine in the new location. It looks to be about the right size. Whether it will work or not depends on whether the bolt will fit the water pump hole.
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02:38 PM
Mickey_Moose Member
Posts: 7549 From: Edmonton, AB, Canada Registered: May 2001
Should I get rid of the home made one? if you look at the picture right above the covette dash onthis page you will see the home made one. Not the camaro pully? Should I just get rid of it. As you can see in the pic it is bent and not fixable.
The tensioner in the picture is the Camaro one. That is to say the pulley and spring housing that is right after the alternator in the above picture.
The bracket that it is bolted to looks like someone was lazy and took some metal bracket and bent it to hold the tensioner and idler pulley (the last on it the picture).
[vent]Stuff like this has always been my beef with some people working on thier cars, especially when thier attitude is "ah, it's works and is good enough" - too lazy to take the time to do it properly. [/vent]
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02:41 PM
Mar 7th, 2009
sanderson Member
Posts: 2203 From: corpus christi, texas, usa Registered: Sep 2001
I didn't look close enough to notice but I now see as Mickey_Moose has pointed that there is one bracket that is holding both the tensioner and idler. Why don't you remove the bracket and post a picture. Then we can see what was done and if there is any chance of modifying what you already have to suitably hold just the tensioner. The idler should get moved to the water pump hole.
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02:43 PM
sanderson Member
Posts: 2203 From: corpus christi, texas, usa Registered: Sep 2001
[vent]Stuff like this has always been my beef with some people working on thier cars, especially when thier attitude is "ah, it's works and is good enough" - too lazy to take the time to do it properly. [/vent]
And then send the new owner out on a 180 mile road trip
You know the more I get into this car, the more I realize that this is going to turn into a "REBUILD" thread. I just dont have the time to get into this. Anyone in the houston area looking to make some cash and get this thing to where I need it. PM me please. I didn't know I was buying a project car. I thought it was pretty much done......
[This message has been edited by TEXASGT (edited 03-08-2009).]
. Do you do all your own work? If you still got one, pm me and ill give you directions up to my shop. 
