1516 code w/engine light

Mleigh3582 · December 21, 2006

Hi, my 2003 GMC 5.3 1500 rig does this event every couple days. It happens at Hiway speeds, the first indicator is loss of power, the engine idles roughly and the throttle won't respond. The engine icon appears as well as a REDUCED ENGINE POWER message. When I pull over and restart it it will act normal and run fine , but the icon stays on for a couple more starts and then it will disappear. I have checked the plug on the TPS and found all to be fine , any ideas ?? Thanks, Mark

Mleigh3582 · February 15, 2007

well i see that you are still trying to fix this problem, mmmmmmmmmmmmm. So you checked that yellow wire? did you find the problem? guess not because it is still happening. Should have just changed the throttle body. Well i guess it's in the dealers hand now. I hope you don't get a big repair bill. If the ESI steps are followed one leads to changing the throttle body. Well good luck my friend and hope this gets fixed soon.

Well to ROYG and all , the dealer installed a new throttle body and 1000 miles later the problem has not reoccured, I want to thank all of you for your input and I will continue to read this site and hope to contribute some , thanks , Mark

Mleigh3582 · January 10, 2007

I have seen as many wiring problems if not more than throttle body issues, w/this code, also along w/the location in the yellow ckt in the bulletin, same ckt found a couple broken behind the intake manifold.

<{POST_SNAPBACK}>

Is that near the firewall, and did you repair it by solder and shrink wrap the area broken only ?? Thanks, Mark

slowpokebanshee · January 10, 2007

actually, I cut out a section around the break, and add fresh wire using two butt connectors, and the style connectors I use are shrink wrap in them, vinyltape after that and no problems

Mleigh3582 · January 5, 2007

Mr 007, thanks very much I will go thru the recommendations you gave me this weekend. I'm glad this info exists as I've been racking my noodle to put a cause on these events, Mark

<{POST_SNAPBACK}>

Just an update and observation of my dilemma. I purchased a Innova 3100 Code Reader and I'm seeing the following: one of the I/M Monitors is flashing, it's the EV symbol and I'm assuming it means it is the Evaporative System, (EVAP). This is flashing everytime I check the system and find the 1516 code. I'm also looking at the intake manifold and I see a loosley fitting valve standing upright and mounted to the intake right behinf the Throttle Body, is it suppoed to fit like that ?? The sticker on the fan shroud says it is a Evap Cannister Purge Valve. I'm wondering if this is part of my issue ??? Thanks for everybody's help, Mark Leigh

royg · January 5, 2007

you still trying to fix this problem? You should have spent the money on a throttle body assy. I have had 4 trucks with this code and the reduced engine power on the DIC. All of them have new throttle body assemblies and still running today without the code comming back. The throttle body costs about 150$. So keep on checking your wires hope you find it. If you follow ESI you will probably end up with the diagnosis replace throttle body.

skills4lou · December 21, 2006

Before you go throwing parts at it, get the codes read, and see what the computer can tell you. Use that info to make your next decision

Mleigh3582 · February 7, 2007

actually, I cut out a section around the break, and add fresh wire using two butt connectors, and the style connectors I use are shrink wrap in them, vinyltape after that and no problems

Just an update, I continued to drive it and have it occur now and then , no reason in particular, so I finally had it happen at 15 mph in town driving twice in 10 minutes and then took it to the dealer, they reprogrammed the unit and the truck ran better than it had in a while, but after a wek it appeared again, so I have had it at the dealer for days now and they are driving it several times a day with the recorder plugged in but it won't reoccur , of course, the dealer says they are now searching a database for histories ???? I have mentioned the TBS several times but they are hesitant to switch , they have went through the bulletins like are posted here, patiently waiting, Mark

royg · February 7, 2007

well i see that you are still trying to fix this problem, mmmmmmmmmmmmm. So you checked that yellow wire? did you find the problem? guess not because it is still happening. Should have just changed the throttle body. Well i guess it's in the dealers hand now. I hope you don't get a big repair bill. If the ESI steps are followed one leads to changing the throttle body. Well good luck my friend and hope this gets fixed soon.

royg · February 16, 2007

hip hip hooray! good finally got it fixed. Just curious how much was the bill?

Mleigh3582 · February 16, 2007

hip hip hooray! good finally got it fixed. Just curious how much was the bill?

The Throttle body and install, along with 50 miles of driving it with the recorder on, updating the onboard computer, inspection and testing the wires and and grounds, was 650.00 ------------------

slowpokebanshee · January 9, 2007

I have seen as many wiring problems if not more than throttle body issues, w/this code, also along w/the location in the yellow ckt in the bulletin, same ckt found a couple broken behind the intake manifold.

ChevyTech007 · December 22, 2006

Subject: SES Light And Reduced Engine Power DTC P0120 P0220 P1516 P2135 - keywords accelerator actuator APP blade body connector connection DTC L33 L59 LH6 LR4 LM7 LS1 LS2 LQ4 LQ9 module position reduce sensor #PIP3089B - (10/31/2006)

Models: 2004-2006 Buick Rainer

2005-2006 Cadillac CTS-V

2003-2006 Cadillac Escalade

2003-2006 Chevrolet Avalanche, Corvette, Express, Monte Carlo, Silverado, SSR, Suburban, Tahoe, Trailblazer

2003-2006 GMC Envoy, Savana, Sierra, Yukon

2003-2006 Hummer H2

2005-2006 Pontiac GTO

Equipped with a 4.8 5.3 6.0 or 7.0 V-8 Engine

--------------------------------------------------------------------------------

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

A vehicle may be brought into the dealer for a reduced power message, and DTCs P0120, P0220, P1516, P2101, or P2135.

The Throttle Actuator Control (TAC) / throttle body type trouble codes, may be caused by a loose wiring crimp at the throttle body connector, or a broken throttle body circuit.

Recommendation/Instructions:

Complete the current SI diagnostics for any symptoms or trouble codes found. If a intermittent T/P or TAC module type code is occurring complete the inspections below.

Inspect all related throttle body terminals for a loose wiring crimp. The loose crimp may be difficult to find, and the poor connection will be between the terminal and the copper strands of the wire. Wiggle test the individual throttle body circuits to see if the concern can be duplicated.

Inspect the related circuits for broken wires inside the insulation. The outer wire insulation may look fine, but the internal copper strands may be partially broken. Breaks in the wires usually occur within 1 to 4 inches of the throttle body connector. Wiggle testing may also induce a trouble code to set.

On C/K trucks complete SI procedures for voltage drop on grounds G103 and G104. Grounds G103 or G104 may be loose or corroded.

If a terminal crimp or a broken wire has been found, repair or replace only the circuits involved. There is a throttle body pigtail connector available through GMSPO, but installing this pigtail connector may cause other intermittent TAC module/TP codes at a later date. If this pigtail must be used, please follow the SI procedures for Splicing Copper Wire Using Splice Sleeves. (the proper Kent-Moore crimping tool must be used for this repair)

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

royg · February 16, 2007

Holy sh--!

Mleigh3582 · December 22, 2006

Mr 007, thanks very much I will go thru the recommendations you gave me this weekend. I'm glad this info exists as I've been racking my noodle to put a cause on these events, Mark