Diagnostic help would be appreciated , BUT ......... read the entire description of symptoms and diagnostic steps taken so far , first , before posting !
If you have nothing intelligent to add , don't bother posting !
Here's the deal ........
1994 YJ w/ 2.5 , it came home on the tow truck last night , has become hard to start recently , now it won't start at all .
I have a Factory service manual , a Haynes manual ( crap!) , an OTC enhanced 4000 scan tool w/ appropriate cartridges , an OTC digital multimeter , a good handle on electrical and vehicle diagnostics w/ several years experience.
Today I checked for spark @ #1 plug wire , had none , checked the coil , it's fine , I can enter a actuator diagnostics mode with my OTC scan tool and make a spark when a spark plug is connected to the lead on the coil , I can crank the engine with spark plug connected to the coil wire and make a spark that way too . I have back probed the coil connector , the cam position sensor ( dist.) and the crank position sensor , using my digital multimeter to test voltages and observe triggering events while cranking , as per the factory service manual . Additionally , using my scan tool , in the test actuator mode , I can hear the automatic shut down relay operate , the injectors , and can test the tach , the shift light as well as a few other relays . I have disconnected the PCM connector to visually check for bent pins or damage.
I should add , since I began driving this thing last August , it has , on occasion / intermittantly , at start up , exhibited rough running characteristics , sputtering , unable to take any throttle or build RPM . To correct the problem you simply shut the engine off , re-start and it runs fine ! . It would only behave this way once in a while.
Is this related to the no start ? described above ?
My scan tool is showing one trouble code only , ..... # 33 , this Jeep does not have air conditioning , so a code #33 can be ignored , you could erase it , but it would be back as soon as you started it again , ..... um ..... if it ran
Any ideas ?
A Further symptom , just brought forward by the co-driver , ...... the other day , on the way to work , she noticed the tachometer stayed at 1000 , then it started working properly.
I'm thinking the PCM ( powertrain control module ) is toast , probably a dealer item and not cheap , also , I'm not a parts changer type , ..... guessing what the problem might be , then throwing new parts at it till it runs , not fully understanding the problem or what fixed it , ........... so I'm not about to run out and buy a PCM , to see if that will fix it , borrow one ......... I could dig that !
HELP ! this thing is a DD it needs to be running , every day !!!!!!
If you have read this far , go ahead and post , think carefully about your reply.
