Code U1016 and Hard to Start
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
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From: SoCal
Code U1016 and Hard to Start
Sometimes when I try to start the car after it has warmed and been driven it will rev up and then RPM will drop below 400 and it stalls out.
It eventually starts after one or two attempts or if I give it throttle.
When it happened today (first time in 10 days) it threw a code U1016.
This NEVER happens on cold starts!!
This has been happening since new feul pump, FLP tranny and torque converter installation. Never happened before.
Dealer says new feul pump is fine.
Tuner adjusted tune and has been better.....may just need another adjustment.
But thought I would check here to see if any other issues could cause this or if dealer is full of ****.......what do ya think???????
DH
It eventually starts after one or two attempts or if I give it throttle.
When it happened today (first time in 10 days) it threw a code U1016.
This NEVER happens on cold starts!!
This has been happening since new feul pump, FLP tranny and torque converter installation. Never happened before.
Dealer says new feul pump is fine.
Tuner adjusted tune and has been better.....may just need another adjustment.
But thought I would check here to see if any other issues could cause this or if dealer is full of ****.......what do ya think???????
DH
Race Director
Joined: Nov 2003
Posts: 12,346
Likes: 5
From: Mustang OK
Which module(s) are reporting the U1016 and is is the suffix code showing this DTC to be current (C) or history (H)?
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
Race Director
Joined: Nov 2003
Posts: 12,346
Likes: 5
From: Mustang OK
Which module(s) are reporting the U1016 and is the suffix code showing this DTC to be current (C) or history (H)?
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
The U1016 DTC may or may not be connected to your starting problem, but one really needs to know which module(s) are reporting that code to help make that determination.
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
The U1016 DTC may or may not be connected to your starting problem, but one really needs to know which module(s) are reporting that code to help make that determination.
Last edited by GrayC5; Nov 14, 2005 at 01:00 AM.
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 231
From: SoCal
Originally Posted by GrayC5
Which module(s) are reporting the U1016 and is the suffix code showing this DTC to be current (C) or history (H)?
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
The U1016 DTC may or may not be connected to your starting problem, but one really needs to know which module(s) are reporting that code to help make that determination.
DTCs U1001-U1254 are lost communication error messages. The C5 modules are connected via a class 2 serial data circuit. Each module on the class 2 serial data circuit which is powered and performing functions that require a detection of a communications malfunction is required to send a Node Alive message every 2 seconds. When no message is detected from a module in 5 seconds a DTC will be set. The last 3 numbers in the DTC is the ID number of the module that is not communicating. (e.g., U1016C - In this case 016 is the module ID for the PCM.)
The U1016 DTC may or may not be connected to your starting problem, but one really needs to know which module(s) are reporting that code to help make that determination.
The code was U1016 H from the RFA module (last one as you page thru modules).
DH
Advanced
Joined: Sep 2004
Posts: 99
Likes: 0
Originally Posted by Dirty Howie
Sometimes when I try to start the car after it has warmed and been driven it will rev up and then RPM will drop below 400 and it stalls out.
It eventually starts after one or two attempts or if I give it throttle.
When it happened today (first time in 10 days) it threw a code U1016.
This NEVER happens on cold starts!!
This has been happening since new feul pump, FLP tranny and torque converter installation. Never happened before.
Dealer says new feul pump is fine.
Tuner adjusted tune and has been better.....may just need another adjustment.
But thought I would check here to see if any other issues could cause this or if dealer is full of ****.......what do ya think???????
DH
It eventually starts after one or two attempts or if I give it throttle.
When it happened today (first time in 10 days) it threw a code U1016.
This NEVER happens on cold starts!!
This has been happening since new feul pump, FLP tranny and torque converter installation. Never happened before.
Dealer says new feul pump is fine.
Tuner adjusted tune and has been better.....may just need another adjustment.
But thought I would check here to see if any other issues could cause this or if dealer is full of ****.......what do ya think???????
DH
http://www.gearchatter.com/viewtopic10635.php
Good Luck
Leo3
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Originally Posted by Dirty Howie
Thanks for getting back to me.......
The code was U1016 H from the RFA module (last one as you page thru modules).
DH
The code was U1016 H from the RFA module (last one as you page thru modules).
DH
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Are you SURE that there are not any other DTC codes?? For your car to idle like that indicates that you have a PCM problem, air leak or fuel related issue of some sort. Do you have any MOD's?? Have you done any repairs in the receint past??
BC
BC
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 231
From: SoCal
Originally Posted by Bill Curlee
Are you SURE that there are not any other DTC codes?? For your car to idle like that indicates that you have a PCM problem, air leak or fuel related issue of some sort. Do you have any MOD's?? Have you done any repairs in the receint past??
BC
BC
Yes I have mods (see below)
Yes, as stated above I have had FLP tranny, Vigilante TC and dealer replaced feul pump before this started to be a problem
The car idles fine (750rpm) all the time and NEVER does this on cold starts.
I am trying to eliminate any possiblities other than needing a tune adjustment.....like bad feul pump or air leak that would act up only on a hot start and then only intermittantly.
PS: Thanks everybody else for your input
DH
Last edited by Dirty Howie; Nov 14, 2005 at 04:31 PM.
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Lets start where the dealer was last!!! 
Recommend checking the fuel pressure at the fuel rail when you are having the failure to start issue. When you turn the key to "ON" you should hear a low pitched hum that runs for about 8- 10 sec. That is your fuel pump running to charge the fuel lines.
The pressure should remain constant and should not leak off. You should see right around 55 ish psi. Im sure some one will jump in and give you the exact pressure.
If your loosing pressure or your pump has a loose electrical connector and is cutting out, you can see hard starts and engine stumbling. It womt set codes either. The U code that your seeing is a fluke and has nothing to do with your problem.
BC
Recommend checking the fuel pressure at the fuel rail when you are having the failure to start issue. When you turn the key to "ON" you should hear a low pitched hum that runs for about 8- 10 sec. That is your fuel pump running to charge the fuel lines.The pressure should remain constant and should not leak off. You should see right around 55 ish psi. Im sure some one will jump in and give you the exact pressure.
If your loosing pressure or your pump has a loose electrical connector and is cutting out, you can see hard starts and engine stumbling. It womt set codes either. The U code that your seeing is a fluke and has nothing to do with your problem.
BC
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 231
From: SoCal
Originally Posted by Bill Curlee
Lets start where the dealer was last!!! Recommend checking the fuel pressure at the fuel rail when you are having the failure to start issue. When you turn the key to "ON" you should hear a low pitched hum that runs for about 8- 10 sec. That is your fuel pump running to charge the fuel lines.
The pressure should remain constant and should not leak off. You should see right around 55 ish psi. Im sure some one will jump in and give you the exact pressure.
If your loosing pressure or your pump has a loose electrical connector and is cutting out, you can see hard starts and engine stumbling. It womt set codes either. The U code that your seeing is a fluke and has nothing to do with your problem.
BC
Recommend checking the fuel pressure at the fuel rail when you are having the failure to start issue. When you turn the key to "ON" you should hear a low pitched hum that runs for about 8- 10 sec. That is your fuel pump running to charge the fuel lines.The pressure should remain constant and should not leak off. You should see right around 55 ish psi. Im sure some one will jump in and give you the exact pressure.
If your loosing pressure or your pump has a loose electrical connector and is cutting out, you can see hard starts and engine stumbling. It womt set codes either. The U code that your seeing is a fluke and has nothing to do with your problem.
BC
Thanks for your thoughts. And I will get my tuner to check for pressure. Should I here the hum from the feul pump behind me or some thing in the engine bay. Should I turn my key to on for a few seconds always before starting......I never do....I just quickly turn it to on. BTW the reason they replaced the pump was because I was complaining of it occasionally making a high pitched humming noise.....it doesn't anymore.
Thanks for your help......
DH
