Hey guys what's up? I just installed a "JUN" chip in a "PR4" ECU i bought off ebay about a year ago but i lost the resistor that came with it. iv'e never done much soldering but i took my time and did a decent job. I didn't put a jumper in and went to start it and it idled for a second and died. i opened an old stereo and found a resistor similar and tried it and it runs but won't ReV higher than 4K and is stuttering, so is there somewhere i can buy a resistor or what can i use to replace that. Any info would help i don't know s*** about this thanks.

 

Contact Chris at Xenocron.com

 

Your "JUN" chip is crap. Get a chip with a basemap for your car/engine..

 

do i need the resistor "the jumper" in to for it to run right or does that really not matter to much. without the jumper it didn't run and with a different jumper "resistor" is ran but didn't rev over 4K so i think i need to find the right resistor that come with it.

 

Which resistor are you even referring to?

 

This chip is basically what i have, i need the resistor or something to replace it.


http://www.c-speedracing.com/temppics/chips/jun.jpg

 

If this is an OBD1 ECU, I assume you mean the resistor for R54?

its a 1.0k ohm resistor, go to radioshack and pick one up.

If this is an OBD0 PR4...im not sure what to tell you

Take some snaps and post them up to show us what you have

 

Here is the ecu with the JUN chip and the resistor needs to be jumped above it on J1 or R54 not to sure on what one, there's already one there but the wrong one tying different things.
" i don't know if the link will work haven't done this before" can't post pics directly

http://www.facebook.com/photo.php?fb...00000753936507

here's the whole ECU "not sure OBD0 or OBD1"

http://www.facebook.com/photo.php?fb...00000753936507

 

upload it on photobucket and paste the img code here

 

here is the full ECU not sure OBD0 or OBD1



here is the ECU with the chip in it

 

It's an obd1 ecu. Why did you solder the chip into it?

Normally we solder in a 28 pin zif socket in so that the chip can be removed in and out without having to desolder and solder everytime.

Like so:

 

one of the pins broke off the zif socket so i was like F*** it and just put it in, but other than that how's it look what do i need to do?

 

Buy a new zif socket and install it. Then get a new chip with the proper basemap for your motor.

www.xenocron.com

All you need is under the chipping tab on the website.

You can also send it in to have them do it for you if you don't want to mess it up.

 

You put the 1.2k resistor in the wrong spot. The resistor goes into R54. A jumper or O ohm resistor goes into J1.

 

Let me guess. You're determined to get this to work because you spent a decent amount of money on this JUN map. Chances are, if you want your motor to run right, that chip is going to be ditched anyway.

One of the biggest misconceptions about modding cars is that Chip = HP..

Not so.

Tuning CAN equate to HP. You need your ECU properly chipped to have full tuning capabilities to extract the most usable HP, as well as a smooth power curve.

These Jun/Spoon/Mugen ECU chips are basically useless unless you have a crate motor from any of these companies, or if the basemap is made for a stock engine. They STILL need to be tuned anyway.

The ONLY time I've seen one of these things work is when my buddy put a Mugen ECU chip in his ECU for an ITR motor. He broke 200whp on a dyno day. I can't recall if he actually got it tuned or not.

 

un-tuned ecu chips suck

i speaks from experience

 

It would be nice to get it to work, I've been wanting to install it for a long time, when i bought it the instructions said to put it in no tuning should give 10-20 HP witch would put me close to 200 HP if it works. I'll try what HAMOTORSPORTS said a well see what happends, i'm close to getting it to work i can feel it lol. Do u need a chip to be able to tune your car for the better HP. what would i need to tune for better HP? what else can i use for a jumper for J1 i don't have a 0 hms resistor, i read some where that u can use a wire probably not a good idea i don't know let me know. i have an old stereo that has lot of resistors but i don't know what they are.

Thanks for your info definitely helping.

 

http://xenocron.com/install/1720.htm

There are other EMS that do not require a 28 pin chip.

 

Thanks guys for all your help, i moved the resistor down to R54 and stared my car reved up to 7000 normal, said it's supposed to rev at 8500 redline but i drove it and can tell a difference a bit more power. do you think i still need the jumper on J1 above the resistor? maybe that will finish it and let it rev to the limit 8500, let me know what u think.

 

Like the ecu I posted above I just used an 820ohm resistor. Works fine for me and never noticed anything different. But if j1 is not in properly; the ecu will still be reading the stock map instead of the map on your 28 pin chip.

 

Without j1 jumpered, you are running the stock map for that ecu...

 

what can i use as a jumper or where can i buy a O ohm resistor. radioshack maybe, let me know i want to see the results.

 

Dude... 0 ohms means 'use a piece of wire', preferably solid and about the right size to fit in the holes you're soldering. If you have any spare resistors you can cut off lead wire from them to make the jumper.

 

Did you look at the link I posted? It tells you exactly what you need to do.

 

By the way, looking at the chip it appears that it could have cold/poor solder joints, either from insufficient heat, solder, or both. If you fix that, you might toast the chip - but as is it could give you grief later if a joint cracks. The value of the socket is that it is much more tolerant of the heat required to solder it in correctly.

All this to say - I second whoever encouraged you to have a professional do the install. If you can't then at least find a friend with a bit of experience.

Good luck