September 2010 Your Jeep

The rear axle on the Toyota is centered. The front had Birfield CV joints in the axleshafts, which aren't really as strong as comparable Dana 44 shafts, but that are arguably stronger than your factory Dana 27 shafts. If you're going to do a T-case swap to a Dana 20 and you don't have to regear the Toyota axles, then by all means go ahead.

However, if you're going to regear, add lockers, narrow, or do any other custom work to the Toyota axles, I'd say it's better to go grab a pair of Dana 44 axles out of a Jeep Wagoneer. The Wagoneer will have 30-spline Dana 44 shafts front and rear. Additionally, if you find a Wagoneer with the Quadra-Trac T-case, it'll have the offset rear Dana 44 axle that will work with your Spicer 18 T-case. The downside to the Wagoneer axle is it requires the springs to be moved to the outside of the frame on the front to clear the pumpkin, and at roughly 58-inches WMS-WMS, they're wider than your factory CJ axles. However, they're comparable in width to the Toyota axles.

How Well for EFI
I read your article about the Powerjection III fuel-injection system and got pretty excited. We bought my wife a '91 Grand Wagoneer with a carbureted AMC 360, and with all the crazy inclines and cold winters here in Utah, could use injection. Unfortunately, we have some very strict counties around Salt Lake City when it comes to emissions and engine modification. You can't do jack to your engine unless your rig is older than 1984. My mechanic told me I could only put a TBI kit on it legally if it came with a "CARB Certificate" (California Air Recirculation Board- I think). Is there a TBI kit that includes that certificate or a way to get a manufacturer to include it so I can put one on? Your insight would be appreciated!
George Bennett
Kaysville, UT

Your best bet will be Howell (howellefi.com). The company lists a 50-state legal Jeep system for '72-'93 AMC 304, 360, and 401 engines under PN K247JPV8 on its website for $1,400 as of this writing.

Cranky YJ
My Jeep won't run at low rpm. It will idle, but when I try to drive it, it dies quickly as soon as the rpms drop between gears. The four-cylinder is on its way out this summer, but want to wheel a bit in mean time. The coil, plugs and wires, cap and rotor, fuel pump and filter, and crank position sensor have all have been replaced. The Jeep is a '90 Wrangler with 145,000 miles and a rebuilt transmission. Is their something I'm not thinking of? Perhaps a sensor? I'm a factory worker with three kids, so I can't keep throwing cash at it in vain. That's for bigger parts!
Mike Garland
Conway, AR

The symptom you're describing sounds like a textbook Crank Position Sensor malfunction, but since you say you've changed it out, it's probably not the case.

First, spray some throttle body or carb cleaner around the vacuum lines with the engine running to see if the rpms increase. If they do, you've got a vacuum leak. That could be exacerbating the problem, but probably isn't the main culprit.

Next, look at the EGR valve under the throttle body. With the engine running, check that the plunger rod actually moves when you stab the throttle. If the EGR valve has stuck open, the vehicle won't run well, if at all, at lower rpms.

Next, check out the idle air control valve (IAC) on the throttle body. To check it correctly, remove the throttle body and hold it upside-down to view the air passage ways. Spray throttle body cleaner to clear out any gunk that may have blocked or limited airflow to/through the IAC. If that doesn't do the trick, rockauto.com sells new IAC valves (PN 19160423) for $119.99. The IAC or EGR are most likely your culprits.

If even that doesn't help, try removing the bulkhead connectors on the driver-side firewall, cleaning them with electrical contact cleaner and a toothbrush, lubing with dielectric grease, and reinstalling. Also, check the computer connections behind the glove box. According to our electrical wizard Trasborg, these connectors often go bad on these Jeeps and can cause problems like this.