truck likes to go...
#1
01-07-2006, 08:36 PM
truck likes to go...
ok so here's my little problem..well not a problem a question...when my truck is in park..or I guess when ever the engine is on...it reves up and then goes back to a regular idle...sometimes it's so strong that if your foot isn't on the brake hard enough it moves forward...IT hink it might have something to do with the throttle..but I am not sure...and I figured I'd give you all something to try and figure out
thanks
Karin
thanks
Karin
#2
01-07-2006, 08:56 PM
RE: truck likes to go...
I have experienced this before with a partially blocked EGR valve. As the valve works, it opens, but never really closes due to the carbon buildup. With the newer engines there is an idle air control valve that maintains a proper idle speed. Most of the time, this condition will cause the truck to almost stall, then surge up to normal idle, but it can go the other way around.
I would grab yourself a new EGR gasket and a can of sensor safe carb cleaner. Spray a good amount (1" deep) into a bowl or something that just the bottom side of the EGR valve will sit in and stay straight up and down. Let it sit in the cleaner for a good hour, then take an old toothbrush and brush out all of the passages.
I would grab yourself a new EGR gasket and a can of sensor safe carb cleaner. Spray a good amount (1" deep) into a bowl or something that just the bottom side of the EGR valve will sit in and stay straight up and down. Let it sit in the cleaner for a good hour, then take an old toothbrush and brush out all of the passages.
#3
01-08-2006, 07:02 PM
RE: truck likes to go...
thanks!!! and with my new tools I got for christmas...it won't be a problem...
oh and it has never gotten close to stalling...it stays at a normal idle speed but speeds up...
thanks!
oh and it has never gotten close to stalling...it stays at a normal idle speed but speeds up...
thanks!
#4
01-08-2006, 07:57 PM
RE: truck likes to go...
If not the EGR valve, could also be an Idle Air Control Valve
I'd take Kyle's suggestion first though, he's way more knowledgable than I am. [sm=hail.gif]
I'd take Kyle's suggestion first though, he's way more knowledgable than I am. [sm=hail.gif]
#5
01-08-2006, 09:01 PM
RE: truck likes to go...
Yes, most definitely could be the IAC valve. It may be a good time to pull off the TB and give it a thorough cleaning. Including pulling off the IAC valve and the TPS. Clean everything with carb cleaner (sensor safe stuff) and pay close attention to the port that the IAC valve goes to. Clean the seal surface and the pintle very well. You don't have to worry much about the tb gasket as it isn't a gasket, but an o-ring, needing only a nice wipe down with some clean motor oil before putting it back together.
#8
01-11-2006, 11:38 AM
RE: truck likes to go...
EGR = Exhaust Gas Recirculator
It is there to push some of the exhaust gasses back into the intake. The EGR serves one purpose and one purpose only. That purpose is to reduce Oxides of Nitrogen (NOx). Undernormal combustion, Nitrogen(N2)Oxygen (O2) in the air and Hydrocarbons (HC) in the fuel combine into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged. Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms Smog. Since exhaust gas is inert (very stable) it doesn’t burn again. So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen doesn’t react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog. Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber.
It is there to push some of the exhaust gasses back into the intake. The EGR serves one purpose and one purpose only. That purpose is to reduce Oxides of Nitrogen (NOx). Undernormal combustion, Nitrogen(N2)Oxygen (O2) in the air and Hydrocarbons (HC) in the fuel combine into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged. Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms Smog. Since exhaust gas is inert (very stable) it doesn’t burn again. So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen doesn’t react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog. Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber.
#10
01-11-2006, 03:39 PM
RE: truck likes to go...
ORIGINAL: swartlkk
EGR = Exhaust Gas Recirculator
It is there to push some of the exhaust gasses back into the intake. The EGR serves one purpose and one purpose only. That purpose is to reduce Oxides of Nitrogen (NOx). Undernormal combustion, Nitrogen(N2)Oxygen (O2) in the air and Hydrocarbons (HC) in the fuel combine into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged. Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms Smog. Since exhaust gas is inert (very stable) it doesn’t burn again. So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen doesn’t react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog. Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber.
EGR = Exhaust Gas Recirculator
It is there to push some of the exhaust gasses back into the intake. The EGR serves one purpose and one purpose only. That purpose is to reduce Oxides of Nitrogen (NOx). Undernormal combustion, Nitrogen(N2)Oxygen (O2) in the air and Hydrocarbons (HC) in the fuel combine into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged. Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms Smog. Since exhaust gas is inert (very stable) it doesn’t burn again. So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen doesn’t react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog. Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber.