Truck Tech

 

 

Hey Roger,

I’m going to the boneyard soon.  Do you know the lengths of the inner axles for a mini-truck straight axle?  I don’t want to get FJ-40 axles!!  Thanks.  WWG65

Hi WWG65:

The mini-truck front inner axle shaft lengths are 15-1/4” and 31-1/2”.

·        Roger

 

 

Hi Roger;

I have a 94 4wd p/u w/ 22re.  My engine runs great, except for when it is idling and I depress the brake pedal.  The engine then idles really weird, kind of a strong then weak then strong then weak, so on and so forth.  It never cuts out, though, and continues to idle normally when I take my foot off of the brake.  I’ve only noticed this after driving, like at a stoplight.  Thanks; Jason McDannold

Hi Jason;

Assuming there are no vacuum leaks, such as in the brake booster, it’s likely because your idle speed is set too high.  I can exactly duplicate this “problem” in my ‘85 by bumping up the idle speed to a bit over 1000 RPM and it’ll act as described.  Turn the idle speed back to normal, and it works fine.  It’s really not a problem, its supposed to work this way and if everything is set properly, and you won’t have the “problem”.

Why is this the case?  Because the ECU has logic built in that says if you hit the brakes and the engine is turning over 1000-1100 RPM, it’ll cut the fuel to the injectors in an attempt to help you stop faster.  After all, no sense pumping gas into the engine when you are braking to a stop.  So idle rises, fuel is cut, idle falls, fuel restored, idle rises, etc.  Turn the idle back to 850-900 RPM where it’s supposed to be and it’ll get back to normal.  Idle speed is adjusted with the large slotted screw atop the throttle body.  Turn it in to lower the amount of air passing through the throttle body at idle (and thus lower the idle speed). 

If you don’t want to do that or it doesn’t fix the problem, here’s a more drastic fix:

http://www.geocities.com/toyotashawn/bizzareidle.html

Which basically involves cutting the wire that feeds the brake light signal to the ECU.  Without that input, the ECU will never know you are braking, so it’ll not be able to cut off the fuel injectors.

·        Roger

 

 

Hi Roger;

Hey, I would like to know what is the best CB antenna for a 40-channel CB radio and the best way to put it on my car.  And I have another 40 channel CB radio that I will be keeping inside and I need to know what is the best antenna for it and how do I talk to people from Tulsa OK or some where else and I’m for Allen TX.

Thank you if you can help, Marcus Brewer

Hi Marcus;

I run a FireStik-II on my 4Runner, it works well, easy to adjust/tune, very rugged and can handle extra power if needed.  I describe how I installed it and the radio on my web page, below:

http://www.4crawler.com/4x4/CheapTricks/CBantenna.shtml

Most important is that the antenna has a good RF ground connection and that it is not blocked by too much body sheet metal.  Also, invest in an SWR meter (Radio Shack has one for under $20) and tune it up well.  For the vehicle antenna, if you intend to go on any organized 4WD runs, be sure to check with the 4-wheeling organization to see if they have any antenna length restrictions.  For example, in California, the California 4-Wheel Drive Assoc. (CA4WDC) limits antenna lengths to 52” (that is why I installed a 48” antenna instead of something longer).  For the base station, a good ¼-wave antenna (108”) is a good option.  You can search the web for lots of information on buying or building a base station antenna.  Again, be sure to tune it up with the SWR meter before you try transmitting with the radio.  Too high an SWR can damage the radio’s output section.

·        Roger

 

 

Hi Roger;

The book shows doing this with a spring tensionometer. I went to 2 auto parts stores and nobody every heard of such a tool and couldn’t find it in the catalog. Is there another way to do this like the old way of tightening then loosening ¼ turn?  Thanks, Chuck

Hi Chuck,

I offer a few other techniques on my axle rebuild page:

http://www.4crawler.com/4x4/CheapTricks/AxleRebuild.shtml#Rebuild

One is to use a plain old spring-type fisherman’s scale, or the other is to use a torque wrench and a tightening/loosening sequence.  I’ve used both techniques and find they work great.

·        Roger

 

 

Hi there,

I am in the process of rebuilding my 22r, and am looking for any references containing info on the oil gallery plugs.  I believe the machine shop that did my block has left one out, as I have no oil pressure.  I found the one on the right side, and the one in the back of the block.  Do you know if there should be one somewhere under the timing cover?  The engine was reassembled right, so it has to be something the machine shop did.  Can you help me out?  Thanks,  CW2 Darren P. Reese

Hi Darren;

For the detailed information you are looking for, I would recommend getting a copy of the Factory Service Manual (FSM) for your year and model vehicle.  I list some sources for the FSM on my web page:

http://www.4crawler.com/4x4/FSM.shtml

·        Roger

 

 

Roger,

 

I just had my 85 xcab/efi smogged. It almost didn’t pass. The CO is fine at both idle and rpm. HC’s are way high at idle (220) but fine at rpm. Truck was tuned prior to test and I did an oil change. I also retarded the timing to 2* static. My air/fuel meter suggests the Ox sensor is functioning properly and it’s an OEM sensor. I’m suspicious it’s the CAT.

Over the last six years the HC’s have been climbing suggesting a slow, progressive failure. Other numbers have also risen, but not as rapidly. Do you have any ideas?  The only two devices I’m aware of that control HC’s are the CAT and the PCV. I didn’t change the PCV, and don’t suspect it as a problem.  As far as NOx, New Mexico doesn’t test for NOx so I have no idea what the number is.  Since the EGR is new I suspect it’s fine.   Thanks, Pappy

Hi Pappy;

I’m certainly no smog expert, but I think your suspicions regarding the catalytic converter are well founded.  I think they tend to slowly lose efficiency at removing pollutants.  Also, you might consider setting the static timing back to the recommended 5* BTDC.  Here in California, where I live, some folks try to retard timing a little to reduce NOx emissions, by delaying the ignition, the maximum cylinder pressure and temperature is reduced, thus reducing NOx production.  On the other hand, you have less time available to burn the gasoline, so it could lead to a slight increase in HC production.

·        Roger

 

 

Note:

If you are searching for, building, modifying, or maintaining a Toyota 4WD mini-truck (Pickup, Hilux, 4Runner, Surf, or Tacoma), send your Truck Tech questions to Roger Brown at <TruckEditor@tlca.org>.  I’ll try to answer your questions with authority!