what engine, bit multiple puzzled

[thanuttiscotsman]

hi there,
now this may sound stupid but ive confused myself over what engine is in my valver. now im pretty sure its the d6c but not entirely. now i know there is a few but what is the easyest way to figure which one i have. here is some details of mine. it is a 1990 non cat without aircon and is alloy block if that helps. now i remember going about figuring out what one i had when i got it but that was 1.5 years ago and ive never thought about it since. you see today my wee go faster chip arrived and im gonna go about fitting it tomo but it says on it its for mi16 pug or gti 16 citro but has written on the front XU9J4 which im pretty sure is an engine type. but i gave the guy my ecu part no before buying it so he could make sure he gave me the right one as he has ones for most makes model and varients of performance engines. any info appreciated.

cheers rossco

[robin hughes]

well it sounds right to me

[thanuttiscotsman]

hey robin,
so i dont have d6c then???:? and so does that mean i can slap the chip in tomo and report back with my results.???

cheers rossco

[Toddman]

Rossco - the mainsite is really quite usefull
Look at Technical and engine

Cheers
Luke

[Kitch]

If your car is a 1990 and has the original engine, it is a D6C.

Both types are XU9J4's, there are two variants.

D6C: Without cat...160bhp

DFW: With cat...148bhp. These only came out in 1992 and are quite rare



In fact there are more variations of the D6C due to having different ECU's etc. Depends if the engine has a knock sensor or not.

[thanuttiscotsman]

hi there,
as far as i know mine doesnt have a knock sensor but if you could tell me how i can check that then that would be great . and so either way does this mean the chip is good for my car? please tell me as im dying to get it in and see the results but dont want to put it in if its not suitable. is it certain ecu systems that do and dont have knock sensors. as in mine is ml4.1 . i thought the only ones fitted with knock sensors were cat models or was it ones with coil packs.

cheers rossco

[Toddman]

Rossco the only thing yu need to check is wether your ecu has 2 rows or 3.
The chip must match the ecu.
2 row ecu was the early one.
The 3 row ecu should have a knock sensor amd the very late cars had the 3 row ecu along with a cat and lambda proble, these were the very last UK cars such like Adrians old silver P2.
Some of the cars have the 3 row ecu but only with knock sensor and these are the D6C engine same powere as the esarly cars but with the more advanced ecu, the knock sensor allows the ecu to adjust ign timing if it detects knocking or pinking.

Cheers
Luke

[Mike E (uk)]

If you put the wrong chip in, the engine won't start.
Luke discovered this recently. Does no damage though.

The engine also won't start if you accidently disconnect the yellow fuel pump feed wire which sits under the ECU.
I found this out the hard way.

[Toddman]

Yep that's right, the chip I had I thought was for a 2 row but it was for a 3 row luckily Mike knew where he had removed the chip from

It also seems that the 2 row ecu has its fuel and ign relays on the inner wing whereas the 3 row has them under the drivers seat with the ecu.

Som enotes here Rossco -
http://bx16valve.com/15.html

Cheers
Luke

[thanuttiscotsman]

hi there,
thanks guys thats all the info i needed, i have removed my ecu before and its defo 2 row and ml4.1 so it is an XU9J4 wich is the right one for the chip.
iam well pleased with that and will have it installed asap and will report on its performance.

thanks again for the help, cheers rossco.

[tim leech]

Someone told me that the early cars phase 1 had a different ECU and were more powerful?

[RobC]

someone was lying to you tim

phase 1 and early phase 2 had the same ECU. later phase 2 had a different ECU but same power rating.

the only 16vs with less power are the ones with the very late phase 2s that came with a Cat.

[tim leech]

Ahh ok!

[jayw]

Someone told me that the early cars phase 1 had a different ECU and were more powerful?

Thats usually what they say when they're trying to sell something...

[Toddman]

Rob is spot on Tim - you should find all the info I have posted up on the mainsite is correct but if any errors have crept in please shout out.
There are a few different ecu codes within the 2 row domain but the differences are tiny just slight differences in the maps due to the cam pulley variations and these differences were to improve driveability the peak power and torque are the same but it is beleived that the 405 ecus did have a slightly different map from the BX as of course we have the HP pump which saps a bit of power so the BX has a more aggresive ignition curve which probably explains why in back to back tests the BX out performs the 405 very slightly within the in gear acceleration tests.

Cheers
Luke