New to Foxbodies... and running into truble on a 92 5.0
11-17-2017, 03:49 PM
#1
3rd Gear Member
Thread Starter
Join Date: Jan 2008
Location: Maryland
Posts: 535
New to Foxbodies... and running into truble on a 92 5.0
Hello,
I have never dabbled in the realm of foxbodies but I am well versed in classic mustangs (65- 70), new edge (1999 - 2004), and the S550s. A buddy of mine bought a fairly priced foxbody with just about all the bolt on goodies one could buy. The car has had two owners. We believe the first owner did all the modifications while the second owner was just an import idiot that bought a mustang. The car needs a lot of TLC and we should have all the minor problems (coolant leaks) buttoned up this weekend. The goal is to get the car back on the road and have fun. However, we are scratching our heads at a few things that I was hoping to get some insight on. Here are the specs of the car:
1992 White LX 5.0
Ported "E7" Heads with knock off 1.6 rockers
B303 cam
Underdrive pulleys
Msd 6al box, MSD coil, MSD wires, MSD distro cap
Cobra Intake (Upper and Lower)
C&L Cold air intake
BBk fuel pressure regulator
3:55 gears
Aluminum Driveshaft
Aluminum radiator
Hurst Sifter
The previous owner (2nd owner) didn't have much of a clue on anything that was done to the car (he only owned it for 3 months before selling). The previous owner said that he didn't race the car, but when my buddy brought the car home, he found a stack of 1/4 mile time slips from MIR. The best the car did was 14.3....... While there is the likelihood of a terrible driver, with all the mods done, I would have expected a lower ET which further believes me that this car is suffering from the lack of a tune/chip.
Question 1: Does the car need a tuner/chip to run correctly with supporting modifications? My assumption with my dealings with the newer mustangs is that the answer is "yes". The car runs pretty rich and will burn your eyes if you are riding in the car. Another assumption that I have is that the original owner must have had a chip but removed it before selling to try to get some extra money..... Why would someone spend all the money for all the mods and not get the car a tuner/chip!?!?!?!.
Question 2: The engine is not original to the car and appears to be a truck engine. The heads appear to be truck heads too that have been ported based on visual inspection. The heads have a weird circular boss that appears to have been used to center a manifold used on the F150s. The boss is located right above the center water passage port on both sides of the engine. This port is partially exposed by the cobra intake when the intake is on the car and is not covered by the gasket either. Will this cause any problems? My assumption is no because coolant wasn't spewing out of there prior to taking everything apart, but thought I would check.
I have never dabbled in the realm of foxbodies but I am well versed in classic mustangs (65- 70), new edge (1999 - 2004), and the S550s. A buddy of mine bought a fairly priced foxbody with just about all the bolt on goodies one could buy. The car has had two owners. We believe the first owner did all the modifications while the second owner was just an import idiot that bought a mustang. The car needs a lot of TLC and we should have all the minor problems (coolant leaks) buttoned up this weekend. The goal is to get the car back on the road and have fun. However, we are scratching our heads at a few things that I was hoping to get some insight on. Here are the specs of the car:
1992 White LX 5.0
Ported "E7" Heads with knock off 1.6 rockers
B303 cam
Underdrive pulleys
Msd 6al box, MSD coil, MSD wires, MSD distro cap
Cobra Intake (Upper and Lower)
C&L Cold air intake
BBk fuel pressure regulator
3:55 gears
Aluminum Driveshaft
Aluminum radiator
Hurst Sifter
The previous owner (2nd owner) didn't have much of a clue on anything that was done to the car (he only owned it for 3 months before selling). The previous owner said that he didn't race the car, but when my buddy brought the car home, he found a stack of 1/4 mile time slips from MIR. The best the car did was 14.3....... While there is the likelihood of a terrible driver, with all the mods done, I would have expected a lower ET which further believes me that this car is suffering from the lack of a tune/chip.
Question 1: Does the car need a tuner/chip to run correctly with supporting modifications? My assumption with my dealings with the newer mustangs is that the answer is "yes". The car runs pretty rich and will burn your eyes if you are riding in the car. Another assumption that I have is that the original owner must have had a chip but removed it before selling to try to get some extra money..... Why would someone spend all the money for all the mods and not get the car a tuner/chip!?!?!?!.
Question 2: The engine is not original to the car and appears to be a truck engine. The heads appear to be truck heads too that have been ported based on visual inspection. The heads have a weird circular boss that appears to have been used to center a manifold used on the F150s. The boss is located right above the center water passage port on both sides of the engine. This port is partially exposed by the cobra intake when the intake is on the car and is not covered by the gasket either. Will this cause any problems? My assumption is no because coolant wasn't spewing out of there prior to taking everything apart, but thought I would check.
11-17-2017, 09:12 PM
#2
What firing order is the engine using??
HO=1 3 7 2 6 5 4 8
Non HO=1 5 4 2 6 3 7 8
Is the engine using a MAF sensor??
In stock form with stock components,a 92 LX 5.0 came with a HO firing order,MAF (mass air) sensor & sequential fuel injection.
Sequential= each injector is fired individually with each cylinder.
The 302 that came in the 87-93 F150's used a Non HO firing order,SD (speed density) & batch fire injection.
Batch Fire= a complete bank of injectors fires each time one of the cylinders on that bank is firing.So if it has a firing order of 15426378,when cylinder #1 (pass side) fires,injectors 1,2,3 & 4 are fired together.When cylinder #5 (driv side) fires,injectors 5,6,7 & 8 are fired together.
Changes can be made of course to use a truck engine in the Mustang,but lets see what the po has goin on before moving on.
BTW- if the truck engine is being used and the correct changes were made and the car is using a A9L/A9P/etc ecm,the first thing I would do is run a koeo and koer test to see if any codes are present.A scanner is not needed.A jumper wire,your check engine light and the following link are all thats needed.
http://sbftech.com/index.php/topic,2471.0.html
HO=1 3 7 2 6 5 4 8
Non HO=1 5 4 2 6 3 7 8
Is the engine using a MAF sensor??
In stock form with stock components,a 92 LX 5.0 came with a HO firing order,MAF (mass air) sensor & sequential fuel injection.
Sequential= each injector is fired individually with each cylinder.
The 302 that came in the 87-93 F150's used a Non HO firing order,SD (speed density) & batch fire injection.
Batch Fire= a complete bank of injectors fires each time one of the cylinders on that bank is firing.So if it has a firing order of 15426378,when cylinder #1 (pass side) fires,injectors 1,2,3 & 4 are fired together.When cylinder #5 (driv side) fires,injectors 5,6,7 & 8 are fired together.
Changes can be made of course to use a truck engine in the Mustang,but lets see what the po has goin on before moving on.
BTW- if the truck engine is being used and the correct changes were made and the car is using a A9L/A9P/etc ecm,the first thing I would do is run a koeo and koer test to see if any codes are present.A scanner is not needed.A jumper wire,your check engine light and the following link are all thats needed.
http://sbftech.com/index.php/topic,2471.0.html
11-20-2017, 10:17 AM
#3
3rd Gear Member
Thread Starter
Join Date: Jan 2008
Location: Maryland
Posts: 535
Hi,
Thanks for the response. The engine has the HO firing order and appears to have all the original mustang 5.0 stuff (computer etc.). I think the engine from the truck was installed as a long block and that's about it. The good news is that I fired up the car this weekend and there are no leaks (fluid leaks) coming from the intake manifold. So I think I solved that problem some of the problems the car originally had but now I have another issue.
New issue:
The car fires up and sounds strong, but the RPMs hang and never come down below 1,700 RPMs. When the engine starts it revs to about 2,200 RPMs and then after a few seconds it drops to 1,700. When we blip the throttle, depended on how hard the blip is, the engine will rev and stay revved at the blipped RPM. So if you rev the car to 3,000 rpm, it will stay at 3,000 RPM and never come down. Without any blip and after a minute or two at 1,700 RPMs the BBK ceramic shorty headers start to glow red. We immediately shut the car off when they started to glow. I used a timing light and tried to time the car the best I could to see if the RPMs would drop, but they would not come down below 1,700 RPM with the timing at about 11 degrees. ( I followed the online video from LMR to time the car).
On the first start of the engine after replacing the manifold gaskets, the headers did not glow but the RPM hanging issue was there. I noticed that the wire connector from the EGR valve was not connected (the vacuum line was connected). I thought this was the issue...... I connected the EGR ware to the harness and now I have the glowing red headers. Do you think with originally having it ERG wire disconnected, I messed something up with the computer and probably need to disconnect the batter for a few minutes?
Based on some research, there could be either a vacuum leak or potentially a timing issue. Prior to removing the intake manifold, the car ran super rich as mentioned in my original post, so I am having a hard time trying to figuring out how it goes from running super rich to running lean enough to make the headers glow. I am about 99% sure the intake manifold gasket it properly installed and there is no vacuum leak coming from there. Having previous experience with classic mustangs, I made up a some guide studs that are inserted in the heads to make sure the gasket doesn't slip and the intake is straight and where it needs to be when dropped into place. I remove the studs once I have about 4 - intake bolts in place. All Vacuum lines appear to be in there proper place. I didn't remove any of the sensors from the Cold air intake nor did I touch the throttle body. Prior to placing the cold air intake back on, I did have my buddy press the gas pedal to ensure the throttle linkage and throttle would open and close without any issue since I had made a slight modification to the throttle linkage bracket to allow the linkage to clear the cobra valve covers. No check engine lights come on either
Any thoughts? Could this be a computer/lack of a tune issue? I have a code reader, do I still need to do the KOEO test? The car prior to fixing all the leaks drove, revved, had no check engine lights, and had no drive-ablilty issues.
Thanks for the response. The engine has the HO firing order and appears to have all the original mustang 5.0 stuff (computer etc.). I think the engine from the truck was installed as a long block and that's about it. The good news is that I fired up the car this weekend and there are no leaks (fluid leaks) coming from the intake manifold. So I think I solved that problem some of the problems the car originally had but now I have another issue.
New issue:
The car fires up and sounds strong, but the RPMs hang and never come down below 1,700 RPMs. When the engine starts it revs to about 2,200 RPMs and then after a few seconds it drops to 1,700. When we blip the throttle, depended on how hard the blip is, the engine will rev and stay revved at the blipped RPM. So if you rev the car to 3,000 rpm, it will stay at 3,000 RPM and never come down. Without any blip and after a minute or two at 1,700 RPMs the BBK ceramic shorty headers start to glow red. We immediately shut the car off when they started to glow. I used a timing light and tried to time the car the best I could to see if the RPMs would drop, but they would not come down below 1,700 RPM with the timing at about 11 degrees. ( I followed the online video from LMR to time the car).
On the first start of the engine after replacing the manifold gaskets, the headers did not glow but the RPM hanging issue was there. I noticed that the wire connector from the EGR valve was not connected (the vacuum line was connected). I thought this was the issue...... I connected the EGR ware to the harness and now I have the glowing red headers. Do you think with originally having it ERG wire disconnected, I messed something up with the computer and probably need to disconnect the batter for a few minutes?
Based on some research, there could be either a vacuum leak or potentially a timing issue. Prior to removing the intake manifold, the car ran super rich as mentioned in my original post, so I am having a hard time trying to figuring out how it goes from running super rich to running lean enough to make the headers glow. I am about 99% sure the intake manifold gasket it properly installed and there is no vacuum leak coming from there. Having previous experience with classic mustangs, I made up a some guide studs that are inserted in the heads to make sure the gasket doesn't slip and the intake is straight and where it needs to be when dropped into place. I remove the studs once I have about 4 - intake bolts in place. All Vacuum lines appear to be in there proper place. I didn't remove any of the sensors from the Cold air intake nor did I touch the throttle body. Prior to placing the cold air intake back on, I did have my buddy press the gas pedal to ensure the throttle linkage and throttle would open and close without any issue since I had made a slight modification to the throttle linkage bracket to allow the linkage to clear the cobra valve covers. No check engine lights come on either
Any thoughts? Could this be a computer/lack of a tune issue? I have a code reader, do I still need to do the KOEO test? The car prior to fixing all the leaks drove, revved, had no check engine lights, and had no drive-ablilty issues.
11-20-2017, 12:44 PM
#4
3rd Gear Member
Thread Starter
Join Date: Jan 2008
Location: Maryland
Posts: 535
Ok..... After spending more time on the internet, I think the previous owner or who ever installed the Ford Racing cobra upper and lower intake didn't plumb all the hoses correctly and I can't find any instructions etc online on how to go about hooking things up. So there are two hoses that run to the underside of the upper intake, One hose goes directly to the PCV valve (the PCV valve does not have the bracketry for any other hoses to connect to it). Then on the end of the upper intake, there is a hose fitting and hose that runs towards the the back of the firewall. And that's it..... Based on what I have read on line, I think the original vacuum plumbing fixtures should have been place on the underside of the upper intake and all tubes hooked back up..... this is not the case for this car.Does anyone have any good links on the routing of the vacuum lines and/or good instructions on how a ford cobra upper and lower intake are supposed to be installed?
11-22-2017, 11:45 PM
#6
A dirty/defective iac valve or tps can cause a high idle.Youll have to test it and the tps with a multimeter. Try cleaning the iac valve too.If the throttle body is dirty,the throttle plate will stick around the edge.Its also possible, the idle adjustment screw on the throttle body is adjusted too far inwards,which increases idle speed.The screw should be set so that idle rpm is between 625-650 rpm,with the iac harness disconnected.If the mechanical setting is too high,it will take away the computers ability to control idle properly.672 rpm is the target mechanical idle setting the ecm needs to see.The ecm uses the iac to control idle from 672 rpm & up,so having the mechanical idle set too high can cause issues. When you disconnect the iac harness, idle should drop drastically or the engine should stall.Thats a sign the iac is working. If idle doesnt drop at all,the iac is suspect. If it drops a little, but its still high,the adjustment screw is most likely set incorrectly or the iac may still be suspect.A base idle reset procedure is shown in the first link below.It should also be done.
The second link is for tps testing.
Make sure the distributor was dropped in correctly.
1) Remove the #1 spark plug & stuff a piece of toilet paper into the plug hole slightly.
2) Use Witeout and draw a line across the harmonic balancer at the 0° & 10° btdc mark.
3) Use a torque wrench & socket on the crank bolt and turn the crankshaft CW until the paper blows out (this indicates youre on the compression stroke) Turn the crank just a tiny bit more until the 0° balancer mark is aligned with the timing pointer then stop.
4) Remove the distributor cap and make sure the rotor is pointing towards the #1 spark plug cap position.The rotor should be pointed just like shown in the picture at the bottom,between the front two upper intake bolts. If not,the distributor is not installed properly.
5) If/once its installed correctly, start it up,remove the spout plug,aim the timing light, rotate the distributor until the 10° mark is aligned with the timing pointer, tighten the holddown bolt & reinsert the spout plug.
Timing set too advanced can cause a high idle.
http://sbftech.com/index.php/topic,1031.0.html
http://sbftech.com/index.php/topic,29736.0.html
Make sure the purge valve isnt stuck open too,which will also cause a high idle.
The second link is for tps testing.
Make sure the distributor was dropped in correctly.
1) Remove the #1 spark plug & stuff a piece of toilet paper into the plug hole slightly.
2) Use Witeout and draw a line across the harmonic balancer at the 0° & 10° btdc mark.
3) Use a torque wrench & socket on the crank bolt and turn the crankshaft CW until the paper blows out (this indicates youre on the compression stroke) Turn the crank just a tiny bit more until the 0° balancer mark is aligned with the timing pointer then stop.
4) Remove the distributor cap and make sure the rotor is pointing towards the #1 spark plug cap position.The rotor should be pointed just like shown in the picture at the bottom,between the front two upper intake bolts. If not,the distributor is not installed properly.
5) If/once its installed correctly, start it up,remove the spout plug,aim the timing light, rotate the distributor until the 10° mark is aligned with the timing pointer, tighten the holddown bolt & reinsert the spout plug.
Timing set too advanced can cause a high idle.
http://sbftech.com/index.php/topic,1031.0.html
http://sbftech.com/index.php/topic,29736.0.html
Make sure the purge valve isnt stuck open too,which will also cause a high idle.
Last edited by wbrockstar; 11-23-2017 at 09:34 AM.
12-06-2017, 06:23 PM
#8
A check engine light doesn't have to be on in order for codes to be present, so yes its always a good idea to pull codes anytime driveability issues are present.As an example, a lean o2 sensor code can indicate a vacuum leak,misfire,fuel system issue,ignition system issue, etc.So one little code can indicate problems with various components and those components can affect other systems.
You can use the scanner to pull codes, but one is not needed.If an issue develops with the ecm signal return circuit or its wire between the test connector and ecm,
the scanner won't trigger the code test anyway,so not using a scanner is sometimes the best way to go.A short jumper wire & the check engine light or a test light are all that's needed.The following link details the steps needed.
Make sure the engine is at operating temp,AC is off & the clutch pedal is floored
before triggering the test.
http://sbftech.com/index.php/topic,2471.0.html
You can use the scanner to pull codes, but one is not needed.If an issue develops with the ecm signal return circuit or its wire between the test connector and ecm,
the scanner won't trigger the code test anyway,so not using a scanner is sometimes the best way to go.A short jumper wire & the check engine light or a test light are all that's needed.The following link details the steps needed.
Make sure the engine is at operating temp,AC is off & the clutch pedal is floored
before triggering the test.
http://sbftech.com/index.php/topic,2471.0.html