autozone.com has wiring diagrams online. Open an account, add your vehicle and go to 'repair manuals', chassis electrical. Not complete but it does show two circuits for the brake switch. On mine the Brown comes from the brake fuse, hot in run, normally closed to purple to ECM F5. The orange...
Bottom two speeds on HVAC did not work--digging after the resistors and found a module directly below the glove box with two push pins to the front of the lower dash. It's about 4" x 4" x 1" and marked QWP. Does any one know what it does/is???
Thanks to yuse guys I figured it out. In the wiring diagrams it shows a red wire from the fuel pump relay that goes to something called the "priming circuit". No other easily available info without $$$ on factory diagram book. Snooping other forums as well as this one indicates that the only...
Thanks matuva, I guess, like alot of newbies here, I missed the prior post. I did so a search but it didn't show it. And thanks to ak and buddy too for their 'beentheredonethat' posts and write ups.
Question---Priming. Wiring shows the lift pump relay connects the pump to a "priming" circuit when off and to the battery when on during start. Where does that priming circuit end up going???? Also, is there a switch or button somewhere to prime it???
My research so far finds very little...
If you are very lucky, a tool exists to push in the small notch from the wire end and release the lug from the shell. In my case, three on the drivers side and the #2 were all broken anyway.
Am being a bit A---Retentive with my truck so checking everything. Was starting OK but more grey smoke than I thought it should have so I got out the meter and checked the glow plugs. Found two on the driver side that were open circuit. Went to the zone and got 8 new GP's, per the various...
Thanks for clarifying code 68 but I don't get any codes of any kind. I put 30 miles on it on the back roads in and out of low range and it acts like the ECM thinks everything is OK.
According to the diesel truck ODBI code list for '94 there is no "ratio" error code. Transmission codes are 28 Range pressure switch error, 68 component slippage, 74 input speed fault.
All shifts are above 3000 RPM even at light throttle and hard enough to rooster tail from all four tires.
If you have the rear wheel ABS then this may help, not valid for the later "all wheel ABS".
The following is a list of the trouble codes for the Rear Wheel Anti-Lock (RWAL) brake system.
Code 1: Invalid code
Code 2: open isolation solenoid or EBCM malfunction
Code 3: open dump solenoid or...
1994 Silverado HD, 6.5THO, in low range the tranny, a 4L80EHD, shift points are very high and very hard. Have read that the ECM should re-program the tranny, also read Tech Bulitin 343 from '99 which says that this happens if the ECM loses the low range switched +12. I know the axle is locking...
Hi Buddy,
I would expect to but don't have a scanner. Was told by Joe at Heath that the ECM samples the Baro for atmospheric pressure every 104 seconds. In the later models that do not use the second MAP the atmospheric pressure is sampled while the glow plug heat is on before start up...
Here is what I found, all the turbo engines have an MAP sensor on the intake manifold to monitor manifold pressure. Some have a second MAP, referred to as the Baro, it is on the firewall drivers side and monitors atmospheric, or Barometric, pressure.
"In vehicles below EPA GVWR weight rating...
Truck came with all maintenance records, guy was anal about it, engine oil and filter at 5k, trans at 10k intervals since new, means you are prolly right. I spose I need to find a kit or a really nice used one. Later on, it will be getting some upgrades but need to build up a piggy bank first.
Could be Bison, will keep an eye on it. If you are right it wll start to bind up again, hope you are wrong tho, I'm hoping it was just sludgy gunk in the bearings.
Have driven it now and can say it made a difference. Used to be able to feel the turbo come in at about 2500, now it feels like it is pulling hard from the git go. No real lag except when cruising at 50 in OD and I mash it. That's even hard to feel due to the kick downs, kind of like the...