4x4 auto 98 blazer will not shift into 3rd or 4th gear

[stuandray]

I drove my blazer to work and it was fine on the way home it would not shift into 3rd or 4th gear. I crawled under and there is a small amount of fluid around the transfer case and axle. At the same time my check engine light came on which was probably a result of the high rpms. the code i pulled was maf or vaf circuit low input. Does anyone out there no if there is anything that could be causing my shift issue on my 98 4x4 chevy blazer 4.3L.

[MT-2500]

If sensor input signals are missing or not accurate it can cause trans to go into limp more/second gear.
You need to start working on that maf sensor signal.
What code no did it have? K&N air filter? Have you got it all hooked up like hoses and clamps and air intake hose?
Try cleaning the maf with electrical cleaner.
MT

[stuandray]

Originally Posted by MT-2500

If sensor input signals are missing or not accurate it can cause trans to go into limp more/second gear.
You need to start working on that maf sensor signal.
What code no did it have? K&N air filter? Have you got it all hooked up like hoses and clamps and air intake hose?
Try cleaning the maf with electrical cleaner.
MT

thanx but the code was prob b/c my air intake was loose I reset the computer and still no 3rd or 4th gear and no other codes

[bcproductionsinc]

It sounds to me like the Transmission Speed Sensor. Is your speedometer functioning? If not, then it's definately your TSS.

[stuandray]

Originally Posted by bcproductionsinc

It sounds to me like the Transmission Speed Sensor. Is your speedometer functioning? If not, then it's definately your TSS.

I have already experienced and dealt with that problem.
Could it be a oil pressure problem or linkage or electronic shift or other sensor problem. Does anyone know if their is anything that could keep the truck from going into 3rd or 4th or am i screwed and need a new tranny.

[laxman21]

I'm sure you have done this, but have you checked the tranny fluid level? How did it look? Any bubbles in it?

[stuandray]

tranny fluid looks and smells normal fluid level is ok also. thanx

[stuandray]

Originally Posted by MT-2500

If sensor input signals are missing or not accurate it can cause trans to go into limp more/second gear.
You need to start working on that maf sensor signal.
What code no did it have? K&N air filter? Have you got it all hooked up like hoses and clamps and air intake hose?
Try cleaning the maf with electrical cleaner.
MT

what is limp more how do you reset

[spasticone]

I am having the EXACT same problem in my 94 blazer. It started less than 30 mins ago. There has to be a solenoid malfuntion or something, but why the tranny fluid smell! Unbeleivable how similar this is to my problem.

[MT-2500]

Limp more was a typo errow.
LIMP MODE!!!!. was what it is. Sorry about that.
If all sensors are not reading right your trans may go into limp mode. Or lock into second gear.
Get it on a good eng/trans capable scanner and see what is going on.
Check sensor readings and check for codes.
To reset it you need to find the problem and fix it and clear codes with a scanner.
Post back any code no.you get.
MT

[stuandray]

Could this be caused by the shift solenoids and if so how do I determine so where are they located

[Brian_D]

Are you sure the problem isn't with 1st and OD instead of 3rd and OD?
In limp/failsafe mode for the 4L60E transmission, you will only have [R] [2] [3] - (3rd gear starts unless the selector is placed in D2 or D1,then it has second gear starts).

refer to this thread for problems with failsafe mode: 4L60E lost first and overdrive

[spasticone]

I think he's sure on that. I'm having the same problem. I can drive off in first and it shifts normally to 2nd. then it searches wildly for 3rd and ends up back in 2nd and so on. It's like 3rd and 4th are just gone... Then... In my situation (not sure about staundry's) If I downshift from OD to 3rd, i can just barely feel it downshift, but it feels like it's barely there. I've been reading on another site ( http://www.atraonline.com/vbulletin/...hp?threadid=49 ) that the 2-3 shift valve could be the culprit. I need advice also on what to check next. Not being the most avid automatic man I need to know what I can check externally.

[Brian_D]

Originally Posted by spasticone

....the 2-3 shift valve could be the culprit.

a bad 2-3 shift solenoid would cause no 1st or 2nd gear

a bad 1-2 shift solenoid would cause no 1st or OD

a bad 1-2 and 2-3 solenoids would cause no 1st, 2nd, or OD

[stuandray]

Originally Posted by Brian_D

a bad 2-3 shift solenoid would cause no 1st or 2nd gear

a bad 1-2 shift solenoid would cause no 1st or OD

a bad 1-2 and 2-3 solenoids would cause no 1st, 2nd, or OD

Do you have any idea what could keep us from getting into 3rd and 4th gear. I have R 1 2 no 3rd orf 4th it start winding out 2nd gear at about 30mph and that is all I can get out of it.