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89 with a rebuilt 94 motor?

sik4wheeler

NAXJA Forum User
Location
Campbell, C.A
So I just finished swaping the 94 motor into the 89 cherokee. I am using the old wiring harness with the complete long block off the 94. I am pretty sure the timing is correct. The jeep idles fine, but when given throttle it sputters and doesnt rev up. Would the TPS casue this? I put on a new TPS, but have not set it up correctly yet. All of this is with the xj in park. Thanks for the help.
 
sounds more like a timing issue more than a tps issue. seems like its 1 tooth off.

you did a long block swap so that includes the block, head, and intake from the 94? correct

what throttle body are you using?

since you are using the renix electronics you need to use the 89 flexplate/flywheel and distributor.
 
I think the 4 bolt throttle body will not work with a Renix set up. I think the signal to the 'puter is different. Otherwize this would be a common swap. It is done using the Renix head on the H.O block but the electronics from the Renix motor must be on the H.O so that means the Throttle body as well needs to be Renix for it to run properly.
 
sounds like your 1 tooth off on the dizzy, but since you havent modified the tps to work with the HO throttle body, its hard to say.

the HO throttle body will work, but the tps needs to be modified. several people have done this although i have not so i dont know exactly how its done, but hesco makes an adapter for the tps or you may be able to find a write up through search.
 
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I tested the MAP and it is good. Also there is plenty fuel pressure and nice blue spark. Tomorrow I am going to swap out the fuel injectorswith some others I know to be good. Does anyone have any other input. thanks
 
sik4wheeler said:
I tested the MAP and it is good. Also there is plenty fuel pressure and nice blue spark. Tomorrow I am going to swap out the fuel injectorswith some others I know to be good. Does anyone have any other input. thanks

is the MAP vacuum line connected to a vacuum port?

about the dizzy, when you put it in the first time you could have been off by 1 tooth and it may need to be reset in the correct position.
 
Everything is connected. It could possibly go one tooth clock wise, but if I did that the rotor would be pointing further away from #1 cylinder. Also, since it's idling great wouldn't that eliminate timing. I pulled #2 & #3 spark plugs out and both were already all black (had carbon) and were real dry (couldn't smell any fuel).
 
If you've messed with the distributor re-index it. Indexing can be a royal bitch to do but is important, also did you use your distributor or a new / used one? I ask because the cam sensor / pickup coil / stator in the distributor has two positions it can live in and it'll play hell on you if it's in the wrong one for your Jeep.

As for the throttle body... An out of spec TPS will not cause that problem, hell my Chief's ECU doesn't even see the TPS sometimes (damn C101!) and it runs just fine.

Last - You are aware that there is no way you're going to pass smog now, right? Running with the HO intake means you don't have an EGR and with an '87 - '90 Jeep that means you're going to get failed on the visual check (they won't even bother hooking the sniffer up).
 
I changed out the fuel injectors with all known to be good ones=no change. Pulled out all six spark plugs and they have a lite coat of carbon and none really had a fuel smell.

What would be the sypmtoms of a bad fuel regulator?
 
I am unsure of the pressure, but with the car on and pressing the shredder valve it shot to the pass. side fender. With the car turned off and waiting a few minutes it let out some , but did not shoot out like before.
 
sik4wheeler said:
I am unsure of the pressure, but with the car on and pressing the shredder valve it shot to the pass. side fender. With the car turned off and waiting a few minutes it let out some , but did not shoot out like before.

To the PASSENGER side fender?

Get a fuel pressure gauge, it's one of the most handy tools you can have for diagnosing problems.

Don't worry about the loss of pressure when it's off, the check valve in the pump is probably leaking (very common) so the pressure is dropping off after you turn it off. For that issue I just turn the key to on, hold until the fuel pump shuts off (a few seconds), and then continue on to Start and the Jeeps start up quick.
 
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