My buddy just bought a 2000 toyota tundra 4.7 4x4. The only problem it has, is it wont idle when its cold. It starts just like a carb. motor would. You turn the key and itll start but cut right off, itll to this about three or four times before itll actually run with you holding the thorttle down a lil bit. It allways idles around 800rpm even when its cold, if it will idle. it never starts up and starts idling down as the motor warms up like my tundra does. any ideas? he says hes not that worried about it since his old truck was carburated and he had to hold down the thorttle a lil bit before it would idle when its cold.
Something is definitely not right. How many miles is on the truck? I would start by cleaning the throttle body/MAF and see if that will help out with the issue. Good Luck!
I had a similar issue with an '92 Tacoma I had with a 22RE throttle body and I while I no longer have the truck or the paperwork I believe it sensor related. I would replace the Mass Air Flow Sensor(shout out to Main70072), the Throttle position sensor, the thermostat and the O2 sensor in the exhaust. This should provide the engine computer with better data on the temp. of the engine as well as the fuel it is being given along with the exhaust it is producing, ultimately telling it the proper idle speed. While I don't remember all the details, I do know that I fixed this problem without spending a lot of money, and without replacing the fuel filter or cleaning the TBI, although I recommend doing both of these given the age of the truck.
I had a similar issue with an '92 Tacoma I had with a 22RE throttle body and I while I no longer have the truck or the paperwork I believe it sensor related. I would replace the Mass Air Flow Sensor(shout out to Main70072), the Throttle position sensor, the thermostat and the O2 sensor in the exhaust. This should provide the engine computer with better data on the temp. of the engine as well as the fuel it is being given along with the exhaust it is producing, ultimately telling it the proper idle speed. While I don't remember all the details, I do know that I fixed this problem without spending a lot of money, and without replacing the fuel filter or cleaning the TBI, although I recommend doing both of these given the age of the truck.
I had the same issue on my older Nissan Maxima and later found out that it was the MAF sensor, replaced it and runs like a champ.
Like "Gnslngr" mentioned above, I recommend cleaning everything first just because you don't know if any of these parts were ever cleaned by the previous owner. Try disconnecting the battery to reset the computer after cleaning to see that that will improve anything. BTW, is the CEL on?
__________________ 2003 white limited stepside with a 5.7 in the engine bay!! 6 speed transmission. LINk G4 Extreme engine controller , PCS transmission controller with tip-tronic control and a couple more options , custom stainless steel true duel exhaust oh yea
allright guys thanks. It has 127,000 miles on it and no CEL. I think were going to try taking my MAF senor out and putting it on his truck and see what happends. Doesnt the MAF sensor, and water temp. sensor control the idle when cold? It runs liked a raped ape still, so it cant be affecting the motor to much. BTW its all stock.
allright guys thanks. It has 127,000 miles on it and no CEL. I think were going to try taking my MAF senor out and putting it on his truck and see what happends. Doesnt the MAF sensor, and water temp. sensor control the idle when cold? It runs liked a raped ape still, so it cant be affecting the motor to much. BTW its all stock.
I think the saying is: like a raped date... Apes stick their own fingers in their a$$....lol....
Last edited by mytundrarocks; 10-19-2009 at 01:29 PM.
I would clean that throttle body. Replace the throttle body gasket if torn or worn out. Go to any auto parts store and pickup a bottle or 2 of throttle body cleaner and mass airflow sensor cleaner.
Replace fuel filter. Only buy a toyota fuel filter.- I have a purolator one on now but my mechanic had to move the fuel lines a little bit since purolator fuel filter is just a hair larger than the toyota one.
Probably your IAC (idle air control) valve. This valve is located on the throttle body and controls the idle speed. If it gets gunked up or quits working it you will run into this problem. I removed the throttle body on my 96 Tacoma and cleaned mine. Works great now.
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Doug Thorley ceramic coated headers, SOS high flow Y pipe, Doug Thorley cat back exhaust, K&N drop in filter, Rev-Tek 2.5" lift kit, diff drop, Goodyear Wrangler's 275/70-17's, Dynoed @ 245rwhp
well I took out my MAF sensor and we tried it on his, but no luck. Wouldnt the IAC valve cause it not to run at all? we didnt clean the thorttle body yet but i pulled off the intake and it looks pretty clean.
Just talked to my buddy with the truck, he said he went to the dealer today and ordered a SST union so he can put a fuel pressure gauge on the truck and drive it and see what the fuel pressure is.
The IAC valve is a computer controlled air flow valve. When the engine is cold, the computer tells the valve to open up more, to allow more airflow, so the engine will idle at a higher rpm until it warms up. Valve opens and closes, according to the computer signal, to keep the engine idling at the correct speed be it hot or cold. If you take the valve apart, it looks like a rotating, slide valve. Mine on my 96 Tacoma was gunked up and did not open or close freely. Cleaned it out with carb clean, made sure it opened and closed freely and tested it using a 1.5v battery. Valve opend and closed depending on polarity to battery which told me it was working properly. Put it back in and it worked perfectly. Engine idles up when cold and idle drops to normal when engine warms up.
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Doug Thorley ceramic coated headers, SOS high flow Y pipe, Doug Thorley cat back exhaust, K&N drop in filter, Rev-Tek 2.5" lift kit, diff drop, Goodyear Wrangler's 275/70-17's, Dynoed @ 245rwhp
well i talked to him again today. He took of the IAC or whatever its called and cleaned it. Probably cleaned it with beer knowing him lol. Anyways he put it back in and now the truck will start right up, and cold idle by itself. The problem is now, is it surges he says. It still has the same amount of power it allways has. His deffination of what it sounds like is the motor sounds like it has a cam in it. He wants me to come over now, apparently it sounds good surging with his exhaust he has on it. Probably not good for it, but he wont listen to me half the time so oh well. I wish these motors had a cam in them that would make them surge/lope, i think that would be sweet, not metioning all the power you would have.
wont idle?
Linear Mode
