Slow Speeds

[BLK HMMWV]

You need to send the IP out to be rebuilt . Replace the injectors.

 

[gcbennet]

I opted to have my injectors and IP rebuilt at a local shop. Replacement injectors are all over Epay, etc but I was supporting local business and getting an impeccable warranty out of the deal.

 

[President Camacho]

I ran the vehicle. I'm able to achieve 45 mph in 1st gear with no sound going into 2nd 3rd or 4th. When I downshift to 2nd I can hear the sound as well as first with the expected jolt of high engine rev and braking accompanying such an action. But from the get go, in 1st, it's the same as overdrive. Any ideas?

 

[President Camacho]

How much was the IP and where'd you send it? Did you get an injector part number/s?

 

[NDT]

Dude, 45 mph in first gear calculates to 5000 rpm. Not gonna happen.

 

[President Camacho]

yeah well if it ain't gunna happen then something's wrong, right? I'm gunna take a video.

 

[gcbennet]

Tranny might need to be rebuilt. When I got my truck a few years back it only had third gear. The other two were sludge in the bottom of the pan.

 

[gcbennet]

First Diesel Injectors in Trenton, ON. 613-392-3636. Great guy and knows his stuff.

 

[President Camacho]

I'll wait for warhorses to throw in his hat. Then I'll look to that. Still don't know where to look for the tps. The manual shows it exploded but not where it's located. See what the man says.

 

[linhster]

If the 4l80e is in "limp mode", you will only get 1,2 and reverse. Limp mode are usually electronic related and it's not getting relevant sensor data. Hence to protect the transmission it will operate in those gears.

 

[President Camacho]

 

[President Camacho]

I love this forum because it's full of knowledgeable individuals. The deficiency lies in the fact that the knowledgeable members who are in the know don't know I'm brand new and what they think would be a complete solution may be China for me. Any effort made to provide me pieces to the puzzle to fill in my knowledge gaps is greatly appreciated and these may come in additional clues as to what service manual to look, where I need to start, anything... I don't know what a limp mode is but it's self explanatory... just what to do about it boots my ass more in the right direction. Where are these sensors in relation to the vehicle? I see the exploded diagram but no idea where it is. I'll return the favor by posting pictures and text as to what I did to help future people.

 

[snowtrac nome]

most 4 l80 limp modes were the result of crappy connections in the battery box not feeding power to the tcm

 

[linhster]

Try these test if you have a multi meter.

 

[Lionel]

Bad battery connections are the root of many evils

 

[President Camacho]

Where is this connector and what side of it will the multimeter read?

 

[President Camacho]

If limp mode operates 1st gear... why am I going 45 in 1st gear?

 

[linhster]

Where is this connector and what side of it will the multimeter read?

Oem location is below the seat on the driver side rear. TCM box is there.

 

[linhster]

If limp mode operates 1st gear... why am I going 45 in 1st gear?

I said 1st and 2nd. Low down and look into the info... Lots out there.

 

[President Camacho]

Low down and look into the info? Dude why am I going 45 in first gear? Low down and look into the info... don't want to burn bridges but after asking my question you might as well as given me a cool handshake and a high five because... while what you said sounds cool, I'm still in the dark.