wont start after engine swap

[Peter and Trent McCormick]

just swapped the motor over to a 99 model engine, have put everything back in the right place (i think) also put a new flex plate on, as the holes for the torque converter bolts had wallowed out, but not the damn thing wont start, seems to have no spark but will crank all day long, the battery has good charge and there is fuel pressure, put the scan gauge on it came up with a p0320 no crank angle sensor reference, but the cas is not that old and worked fine before the swap,

any idea guys? would timing possibly being out cause no spark at the coil?

also its a 98 cherokee and i changed over all the old acc to the new motor, so shouldnt be any difference

[undecided]

Does the flex plate have a reference point for the pickup ?

[brenttj]

have you got the fsm or a manual when we did my mates same thing was happening had to get the timing right pm geroxj

[Easy Rollins 1]

also put a new flex plate on


Yep,pickup places on the flex could be diff,or it's out of alignment with the crank.. :confused:

[junglejuice]

When I put the Zg engine in my Xj I had to swap the flex plates as they are different, I didn't have any trouble with it starting afterwards, maybe I fluked it...
I would try another CPS after double checking that everything is reconnected and the main loom connections are all tight and secure....

[Peter and Trent McCormick]

i visually check the flex plate, but not till after it was installed but looked to be the same, but i did notice when installing it that you couldnt just line any hole up with the threaded ones on the end of the crank there was a slight difference in distance between them, so my thinking was you couldnt muck it up, but that may not be the case,

i have another CAS i was going to try off another AW4 i have here but the plug was different...

thought it might have been a bad cam anggle sensor/ stator but it didnt bring up a P0340 which it should if it was buggered,

I have made sure all the plugs are plugged in the right places, and all the grounds are connected also changed the coil over off my tj still but made no difference, im out of ideas

[BLU-125]

Did you change the ECU?

If so, did you change the SKIM module?

This got me for a while.

[Peter and Trent McCormick]

no didnt change the ECU

[dazza96]

does it have a alarm or imobliser and does the centrl locking still work with the remote
just that me and a mate have just done what you did put a 97 grand motor in to a 96 grand and it wouldnt fire till we worked out the alarm but the funny part is the 96 remote is no good now have to use 97 remote on the 96 and a cant explain it but works fine
cheers daz

[junglejuice]

Did you swap the dissy's over? If so is it 100% correct position wise?

[Peter and Trent McCormick]

yeh i did swap the dizzy over it is quite possible that it not in the right position

[Easy Rollins 1]

yeh i did swap the dizzy over it is quite possible that it not in the right position


Get number one piston to top dead centre and make sure the dissy rotor is pointing to number one lead on the dissy cap


HTH a little,good luck.

[junglejuice]

The FSM describes how to position the dissy, I followed this a few years ago after I removed the dissy and it works quite well...

[Peter and Trent McCormick]

i did this but i will check again to make sure its correct

[ozjeepster]

If you still have the scantool go into miscellaneous in the engine section , look for CPS RE-LEARN the CPS & THE CAS need to know where each other are in relation to No1 being at TDC otherwise it will never fire ;)

[tylerzaath]

i put a v8 in my fj40 a few years ago and had the same issue....
Nearly went mental trying to work out why it wouldn't start and eventually realised that the spark plugs were connected in the wrong order. Checked the correct firing order and it started first go.

Sounded bloody nice too as I hadn't put an exhaust on at that stage!

[Peter and Trent McCormick]

If you still have the scantool go into miscellaneous in the engine section , look for CPS RE-LEARN the CPS & THE CAS need to know where each other are in relation to No1 being at TDC otherwise it will never fire ;)

i dont think this can be done with the 'Scangauge 2'

[Nakkas]

I know these are rare now, but try and find a timing light. Will answer a lot of questions...

[Jimmyb]

I bet on the ECU. I have found throughout the years many different part numbers for them. I had issues with a TJ years ago that the battery had leaked onto the ECU. I got another one from Jeeparts from the year model, but wouldnt fire. I checked the model numbers and they didnt match even through the years did. Anyways long and short of it got one from the US on Ebay and worked.

[ozjeepster]

Scanguage won't cut the mustard with this communication problem you will need a jeep friendly generic scan tool or access to a DRBIII scan tool from a dealership , I had an other one in today at work , the xj had been to 3 other places and they all had no idea that the cps and cas have to know each others position with No1 on TDC even if your dizzy is a hall effect unit it still has a CPS and has to have the re-learn procedure done to it ;)

[junglejuice]

Scanguage won't cut the mustard with this communication problem you will need a jeep friendly generic scan tool or access to a DRBIII scan tool from a dealership , I had an other one in today at work , the xj had been to 3 other places and they all had no idea that the cps and cas have to know each others position with No1 on TDC even if your dizzy is a hall effect unit it still has a CPS and has to have the re-learn procedure done to it ;)

Oh boy, I am so glad I have OBD1!!!!!

[ozjeepster]

OBDII is a piece of cake mate , it's these new grands and other Jeeps / Dodges that scare me lol they are still OBDII but every thing you do has the potential to kill it , everything is linked at some point and it all talks to each other , if ur playin with a WK's ass be sure that it's front end is watching hahahaha ;)

[junglejuice]

lol.... I fitted an OBD2 engine into my OBD1 Xj, works real well and was extremely easy and started first go.....

[Peter and Trent McCormick]

Scanguage won't cut the mustard with this communication problem you will need a jeep friendly generic scan tool or access to a DRBIII scan tool from a dealership , I had an other one in today at work , the xj had been to 3 other places and they all had no idea that the cps and cas have to know each others position with No1 on TDC even if your dizzy is a hall effect unit it still has a CPS and has to have the re-learn procedure done to it ;)

what about something like the snap on soulos or one of them may be able to get access to one of them

[ozjeepster]

what about something like the snap on soulos or one of them may be able to get access to one of them

Snap-on one might do it , we trailed one at work for a few weeks & it seemed to go all right as long as you had the the right chip or model specific key for the reader ;)

[Peter and Trent McCormick]

turns out it was the cas running fine now, ready to go 4wding.... almost...