chrisquested Posted January 2, 2016 Share Posted January 2, 2016 I picked up this 1988 jeep comanche from houston brought it to san antonio. The jeep looks like it has had the wiring harness under the hood replaced along with couple other ptarts. So the jeep did not come with a key so my dad un hooked the ignithion switch and used a screw driving to flip the switch over to turn it on but nothing happened. The jeeo does not turn over "starter does not engage" and the fuel pump does not turn on either. Now with the ignition switch flipped to the on position we do have spark and if we jump the starter we can get the motor turning and by bypassing the fuel pump we can get fuel psito engine. by pouring gas down the throttle body we can get the engine to start up shortly. does anyone know what may be wrong?????? i know its a long shot but i hope i can get this thing running some how. Link to comment Share on other sites More sharing options...
HOrnbrod Posted January 2, 2016 Share Posted January 2, 2016 Could be the ignition switch on the steering column or it's connector is fried, or is mis-aligned. Ignition switch, p/n J3250576, available at Rockauto and others. Connector also.Ignition switch alignment:Fig. 2: Ignition switch rod positioningOn non-tilt columns:Move the ignition switch slider to the OFF unlocked position (move the slider all the way down, then back two clicks). The remote rod hole in the ignition switch slider should now be centered.Insert the remote rod in the ignition switch slider hole and install the ignition switch on the steering column. Tighten the attaching screws to 35 inch lbs. (4 Nm).On tilt columns:Insert the ignition key in the lock cylinder and turn the cylinder to the OFF unlocked position.Move the ignition switch downward to eliminate any slack and tighten the attaching screws to 35 inch lbs. (4 Nm).Install any components removed for switch access. Link to comment Share on other sites More sharing options...
chrisquested Posted January 2, 2016 Author Share Posted January 2, 2016 That is the ignition switch that we are using a screw driving to flip back n forth to try and start it but nothing is happening and there was actually another one in the jeep so we swapped it over and still nothing? Should i try buying a new one just to put in? I am trying to figure out what controls the fuel, starter and injectors because i you can flip the switch to on position and the fuel pump won't kick on and the jeep fires by jumping starter but won't stay running which means injector are not spraying is what i am thinking. I am wondering if it is a possible computer problem by chance? Link to comment Share on other sites More sharing options...
HOrnbrod Posted January 2, 2016 Share Posted January 2, 2016 Check for burnt pins on the connector and make sure the rod is aligned. Link to comment Share on other sites More sharing options...
chrisquested Posted January 2, 2016 Author Share Posted January 2, 2016 If the rod is not aligned what would happen? we took the switch off the steering column and are using a screw driver to flip the switch into the on position or to start it and it won't start. Link to comment Share on other sites More sharing options...
HOrnbrod Posted January 2, 2016 Share Posted January 2, 2016 It sounds like the ignition switch RUN and START contacts are not engaging. Read this thread: http://www.jeepforum.com/forum/f12/basic-maintenance-ignition-switch-1226376/ With a "new" harness, unknown history, and no ignition key you probably have a combination of problems. Link to comment Share on other sites More sharing options...
chrisquested Posted January 3, 2016 Author Share Posted January 3, 2016 So the reason the starter was not engaging when the key was turned is because the wire was not plugged into the fuse block.......so now we have spark, fire, but still NO fuel...... the fuel pump will not come on when the key is turned. my brother in law crawled under tied into the wires and hooked it to the battery and the fuel pump comes on and we get fuel pressure at the rail but only if we hook the pump directly to the pump. so there is something wrong now.... i went to the junk yard and picked up a new computer and it didnt do anything..... Link to comment Share on other sites More sharing options...
Fernando87mj Posted January 4, 2016 Share Posted January 4, 2016 Check to see if the fuel ballast resistor is cracked or broken , jumper those two wires together and see if the jeep starts Link to comment Share on other sites More sharing options...
HOrnbrod Posted January 4, 2016 Share Posted January 4, 2016 ............but only if we hook the pump directly to the pump. Huh? The ballast resistor isn't in the fuel pump circuit until after the engine starts. OP, you need to download the electrical manual and start troubleshooting the 12V pump circuit. Download the 88 electrical manual here: http://www.bteventures.com//88%20FSM.zip Link to comment Share on other sites More sharing options...
chrisquested Posted January 10, 2016 Author Share Posted January 10, 2016 So pretty much the truck turns over but will not start. we have spark/fire to the engine and it will only run if we spray gas or starting fluid into the throttle body. Now we have a basket case here there is some wires that are cut and not going to some places. First thing I am going to do is jump the fuel ballast and see if that helps anything out. If I do jump the fuel ballast will anything happen? can I just remove the ballast and connect the two wires together and call it done? I need to figure out why the fuel pump is not pumping fuel to the rail when key is turned and I need to figure out if the injectors are spraying fuel into the cylinders. Just FYI I live in the san Antonio area and would love some help if anyone is close by !!!!!! thanks again for all info I will be back on it today and this next upcoming weekend working on it some more to see if we can get it going. Really need this jeep to start running so I can make it reliable!!! can't be doing overland trips and offroading for multiple days in a Comanche that don't want to run!!!!!!! Link to comment Share on other sites More sharing options...
Eagle Posted January 10, 2016 Share Posted January 10, 2016 So the jeep did not come with a key so my dad un hooked the ignithion switch and used a screw driving to flip the switch over to turn it on but nothing happened. The jeeo does not turn over "starter does not engage" and the fuel pump does not turn on either. Now with the ignition switch flipped to the on position we do have spark and if we jump the starter we can get the motor turning and by bypassing the fuel pump we c does anyone know what may be wrong?????? i know its a long shot but i hope i can get this thing running some how. The engine starts with all the bypasses, so of course you can get it running. Just be patient and don't break things while trying to fix it. How did your father "unhook" the ignition switch, and how did you bypass the fuel pump? You may have bypassed some important connections. First, are you aware that the key cylinder in the steering column is NOT the ignition switch? The actual switch is the thingie (technical term) shown in Hornbrod's post. It's at the bottom of the steering column, and the key tumbler connects to it by an operating rod. If that rod is out of adjustment, the switch may or may not function. IMHO you should either take your key cylinder to a locksmith and get new keys made for it, or just buy a replacement cylinder (it's a GM Saginaw steering column, so if you can't find one listed for AMC/Jeep, just buy one for a Chevy). Then check the ballast resister, as shown in Fernando's post. You could also check to verify that the fuel pump has a good ground, although being in Texas I wouldn't think rust and corrosion would be a big issue. One step at a time, and keep us posted on how it's going. Link to comment Share on other sites More sharing options...
Marine1Texas Posted January 11, 2016 Share Posted January 11, 2016 A couple of small things, have you done the Cruiser Tips? c101 box can cause many issues! I took mine out and wired direct. I did not see if AT or MT. If MT you can get clutch fluid that spills over and runs down back of fuse box. can cause all kind of funky problems with no power going thru fuses to where it needs to go, corroding the connections at the fuse box Link to comment Share on other sites More sharing options...
chrisquested Posted January 12, 2016 Author Share Posted January 12, 2016 I went ahead and connected the two wires that go to the fuel ballast together. The truck did not come with a key so what my dad did was undo the two bolts holding the igintion switch on then stick a small screw driver in and move the switch up and down same as what the rod would do if the key was turned. Link to comment Share on other sites More sharing options...
cruiser54 Posted January 14, 2016 Share Posted January 14, 2016 http://oljeep.com/gw/elec/cherokee/edge_cherokee.html Link to comment Share on other sites More sharing options...
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