Ford Mustang Forums banner
1 - 7 of 7 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter · #1 ·
I swapped 2.3 to 5.0 Foxbody and did everything by the book. When I start it it runs at 1600 rpms. I messed with the tps and it all checks out. Vacuum lines are all in the right spots without leaks.
Any suggestions are appreciated. This is the last thing I need to do and it’s taking me longer to do then the entire swap combined
 

·
Registered
Joined
·
1,223 Posts
Couple quick checks.
Throttle plate fully closed?
When it's running, pull plug to the IAC and see if rpm drops.
 

·
Registered
Joined
·
9,774 Posts
Unplug the IAC, screw the throttle body screw back out and lower the idle down to where it barely mantains a steady idle. Reset the ECU by disconnecting the battery for 30 mins or so. Plug the IAC back in, hook the battery back up and start the car. Let it idle 2 mins with the accessories off, and then turn them all on.

TPS acceptable range is 0.5 to 1.25 volts. No need to adjust anything in this range. If the idle voltage at startup is outside this range, you will get a code. No code, TPS is fine don't worry about chasing 0.9999999v

Once you get it running well, dump the codes and see what the ECU doesn't like
 

·
Registered
Joined
·
10 Posts
Discussion Starter · #4 ·
Unplug the IAC, screw the throttle body screw back out and lower the idle down to where it barely mantains a steady idle. Reset the ECU by disconnecting the battery for 30 mins or so. Plug the IAC back in, hook the battery back up and start the car. Let it idle 2 mins with the accessories off, and then turn them all on.

TPS acceptable range is 0.5 to 1.25 volts. No need to adjust anything in this range. If the idle voltage at startup is outside this range, you will get a code. No code, TPS is fine don't worry about chasing 0.9999999v

Once you get it running well, dump the codes and see what the ECU doesn't like
I tried all this and it’s still running around 1400 rpms. New pcv
New iac
Checked upper intake.
egr deleted
Smog deleted
Doesn’t seem to have any vacuum leaks either
 

·
Registered
Joined
·
9,774 Posts
Dump the engine codes and smoke test the engine for vac leaks
 

·
Registered
Joined
·
25,617 Posts
I swapped 2.3 to 5.0 Foxbody and did everything by the book. When I start it it runs at 1600 rpms. I messed with the tps and it all checks out. Vacuum lines are all in the right spots without leaks.
Any suggestions are appreciated. This is the last thing I need to do and it’s taking me longer to do then the entire swap combined

Is this a MAF or SD management?

was this donor engine seen running as is? or have you added different parts?
 

·
Registered
Joined
·
332 Posts
Are you seeing your 1600/1400 rpms on the 4 cylinder cluster?

You change the cluster for a proper V8 tachometer..or the dipswitch if there is one?

Just curious if the car is actually running at that rpm or not.
 
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top