Surging Cruise Control

[TCDiesel]

Map sensor... ... ... .

 

[JWChessell]

Anyone have any further info or developments on this problem since the last post of May, 2011 ? My '03 is still doing the same thing, and it's a little bit worse now; much more noticeable after about an hour of driving; turn it off for a half-hour; turn it back on and it'll work OK for about 20 mins . . . and so forth.



??



Thx. JW Chessell

 

[JWChessell]

I just found this post on the 3rd Gen 5. 9 engine forum. Any comments ?



When do injectors commonly start to fail ? I've got 139,900 on the odo.



JW Chessell



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02-26-2011, 12:06 AM #15 (permalink)

steved

Offline

Join Date: Sep 2005

Posts: 6,489



I for one had this without a single mod done to the truck... it was caused (in my instance) by worn or leaky injectors. Once replaced, my cruise is flawless... uphill, downhill, loaded or empty; it is smooth as glass. There was no other change from before to after... the injectors were simply replaced with Flux Is, and my cruise surge was gone.



I added a SmartyJR later, and it had absolutely no affect on the cruise...



My feelings is that the leaking injectors won't allow the ECM to maintain a proper rail pressure, or in other words; the leaky injectors bleed off pressure to fast for the ECM to compensate.



For what its worth, I added cruise to an ST truck... so the surging was "normal" and there upon installation. It was violent at times... and injectors fixed it.



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Last edited by steved; 02-26-2011 at 12:09 AM. .

 

[NavyDood]

I've felt it also since I bought my truck 5yrs ago. It only does it to me in the 45-55 mph range and then it is hit or miss when it happens. I have 130,000 miles on the truck now. I guess my injectors, FCA or Injector pump have been on the fritz for 5 years now.

Almost 172,000 miles and 1 1/2 years later and there is no change in what I posted back in MAR 2010. Still the same.

 

[Prairie Dog]

Strange that so many are affected by this malody but I've never noticed it with my 03 (77K). Kinda sounds like if everything is perfect then it won't do it.

 

[Turbo Kidd]

Sorry, I have not responded to those who have sent me PM's and e-mails... . I now spend my time over at Powerstroke.org and loving my 6. 4! I love having 550 HP at the rear wheels with no issues at all.



Seriously, I love the 5. 9 and always will. I was able to correct my issue. It was a map sensor that caused all of my problems. I tried everything before I figured it out. I was at Dave Goerend's shop getting my transmission done and we started brain storming about it. I / we pulled the map sensor from his truck and tossed it in mine and that was all she wrote. I spent months, and a lot of money looking into other causes.



Good Luck,

Karl (Turbo Kidd)

 

[Prairie Dog]

Map sensor... ... ... .

And the winner is TCDiesel

You really should speak up more Todd! :-laf

 

[TimothyLong]

I never had the surge problem with my '03 and my wife's '04 doesn't have it either. The cruise in my truck just stopped working all together. I replaced the vacuum pump a while back and it helped for a while, but it stopped working again. Just took it to the dealer this evening to get it fixed. I don't use it much, but I sure have missed it when I could have used it.

 

[JJPage]

I replaced my MAP Sensor trying to correct a different problem, and still have the surging, so while it may improve one truck's driving characteristic's, it sure as heck is not the ultimate cure for this common problem.



Like I stated earlier, my truck has done this since brand spanking new, while not towing. Jess

 

[LRuml]

Have you tried replacing the TPS. Mine did the whole surging thing for 6 months. Noticed it more on long trips with cruise control on could be somewhat corrected with light pressure to the gas pedal. Replaced the TPS and 35,000 miles later still no problems.

 

[JWChessell]

I thing we're doing ourselves a mis-service by refering to the problem as "surging," although I did that myself in the beginning of this thread. What I'm experiencing -- and which has been confirmed by several of you -- is that truck-speed DIES momentarily (the opposite of "surging"), then recovers in a second or 1-1/2 seconds, and returns to normal -- only to do the same thing a few seconds later, and the cycle repeats itself over-and-over once the problem starts, which is usually about 1-hour to 1-1/2-hours after first starting out on a long trip.



Notwithstanding that I first posted this inquiry under the heading of "cruise-control," the problem occurs independent of cruise-control; i. e. , the problem occurs whether the truck is under "cruise-control" or "foot-control;" it doesn't matter.



Following one of the member's suggestions concering the MAP sensor, I replace that item. There was no difference in performance; the problem continued as before.



Last week the problem became more pronounced on a long trip from Tucson, AZ to Washington State, almost all of it through the long desert distances of Arizona, Nevada and northern California. During a scheduled stop in Carson City, NV I took the truck to Carson Dodge and discussed it with the mechanics; one (perhaps two) of whom write for TDR. They tested the truck, and checked for error-codes; there were NONE.



They became suspicious of the fuel pump, and tested the pump. Their test found that the fuel pump was puting out only approx 1/2 to 2/3rds of the necessary capacity to operate the injector pump satisfactorily. They recommended that I replace the fuel pump, and opined that this would cure the off-again-on-again speed problem also. I said OK, and replaced the pump ( BIG EXPENSE! ).



On the trip from Carson City, NV to Washington State the fuel mileage increased slightly -- from around 19. 8 MPG to around 20. 2 MPG (hand calc) -- indicating that replacement of the fuel pump had solved SOMETHING.



HOWEVER -- about 6 hours out of Carson City, the off-again-on-again speed problem began to re-occur, and continued all the way home over the course of two days.



Obviously, the problem is not caused by the MAP sensor, or the fuel pump, or the cruise-control module.



Any thoughts? I now have 144,400 on the odometer. DR Member LRUML suggested that the Throttle Position Sensor (TPS) might be the culprit. Is there some way to test that item, as it's fairly expensive to replace -- and -- if I tell the mechanics what to replace, instead of them telling me what they recommend, there's no dealer warranty for failing to correctly diagnose the problem.



??



Thx -- JW Chessell

 

[EDankievitch]

I thought that I posted my findings with my 05 6 speed 4x4. As JWChessell has stated my engine would act as if it would shut down then come back on. Most notice able in cruse but could be felt at other times. After replacing Fuel pressure relief valves and sensors along with the map sensor the problem was still there. I even gave my friend's Smarty a try only to make things worse much worse. At my wits end I changed out the injectors and found number 4 was cracked. the crack would not open up fully unless the engine was hot, so it would run almost normal when it was ice cold. The engine was hot when I removed the injectors and the crack was clear as day. while it was in my hand I watched it close up as the injector cooled off to the point that the crack was no longer visible. I found it strange that the number 4 fuel rail to head tube had cracked about a year before this problem really started to show it self. Only thin I can think is that with the injector over fueling it caused a greater hammering affect on the tube causing it to fail. I think/feel that the computer was seeing cylinder 4 accelerating faster (being over fueled) and would cut back on the fuel thus causing the surge/ momentary shutting down of thew engine. After much shopping around I went with Dynomite Diesel for an injector set. They were the best price and the made sure that I got a matched set (Ok so I went with their stage one set, a slight bit more power slight bit more smoke when cold and better MPG but only by about 1 mpg) Everyone else that offered cheaper injectors for less, were rebuilds not new. Nor were they checked to be a matched set.

 

[blacksheepdiesel]

This problem occurred many times on my '01 which has vacuum cruise, albeit a different vacuum pump than the 3rd gen trucks. It did help to put a red straw from a spray can in the vacuum hose going to the cruise control unit, but the problem still existed. Eventually the TPS went bad and I replaced it. No more problems until the TPS began to go bad about 110,000 miles later. After replacing it the cruise would operate correctly again.

If your 3rd gen truck has the TPS mounted on the cylinder head it is a very cheaply made unit and is prone to a short life. Find a 3rd gen with the same style of TPS that does not exhibit the cruise issue and swap that TPS to your truck to see if it cures the problem. If so then order a TPS from Timbo here on TDR. It is an aftermarket unit that seems to be superior to the factory TPS.

One other item to mention is the the need to obtain a steady speed with your right foot and to set the cruise with the speedo needle on a known stop spot. The speedo has a spot it will stop for each mph and the cruise should be set with the needle on one of these spots after it has been steady on that spot for a few moments, push and release the engage button and then release the accelerator pedal. If the cruise is engaged on one of the spaces between each mph stop spot the ECM can't make up it's mind which stop spot to use and is always going between the two.

Godspeed,
Trent

 

[CPittman]

There is a 10 amp fuse that controls the ABS pump. When this fuse fails you have no speedo and the ABS light comes on as does the "brake" light on the dash. With no speedo you obviously can't set the cruise.



Also, there is a 15 amp in-line fuse from the direct hot off of the battery to the ABS pump. This in-line fuse can have corrosion in it's housing. Also, if your driver's side battery terminal is corroded you may have an intermittent connection problem with power to the ABS pump (the pump is between the driver's side battery and the firewall) Is it possible that you have some bad connection to the 10 amp ABS pump fuse in the main fuse block, or to the 15 amp in-line fuse?

 

[TFrazier]

I've had this issue with my truck since i bought it (5 years ago with 90,000 on the Odometer). I now have 218,000 on it and have over the years replaced: TPS (the one mounted on the top of the engine), Full set of injectors, replaced stock lift pump with FASS 150 GPH, and the COV. I have not yet replaced the FCA but I have one just waiting for me to stop being lazy. I still have the problem. As with others i notice it slightly on level ground but it is most violent (to the point that I shut off the cruise) on a slight downgrade. My boost gauge registers slight change but it is really apparent in my lift pump and rail pressure gauges. my lift pump will jump from 20psi to 16psi constantly and my rail pressure will jump constantly too (I will watch it next time I'm driving so I can give exact numbers on that, I don't remember off the top of my head, I've had the problem so long I stopped noticing).

 

[Alaskaskiff]

I also have a weird cruise problem that may help with one of the above discussions. The cruise will occasionally cut out and regain ... A surge could describe it. It happens ONLY when the wipers are on intermittent and when they activate. There is a direct correlation for me on this. Thiterates outside it is the more often it happens. Occasionally cruise will not recover and it will dump. I have found a ground connection that is suspect on the driver fender. Cleaning it has helped. I may also be losing the wiper module and it may pull too much power for something. When these things happen the speedometer falls off , which is probably the cause for dumping the cruise.

 

[Prairie Dog]

Andy, that would tell me there's a bad ground someplace or even a bad 12v connection (less likely). When the wipers pull current there's a voltage drop - could even be a the ecm.

I would loosen, clean and tighten all the ground connections in the engine compartment and anyplace else under the dash I could find.

The grounds in the eng compartment are many and look like this one to the right of the hood support which is for the ECM, or the one that's just in front of the fire wall in this photo:



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