Help needed, low BHP figure

[Blinky16v 0]

Hi all,

 

I was up at Stealth on Saturday with Vince. I had my 2.0L 16v C dyno'd and was knocking out 138.1bhp.

 

Sounds fine and dandy for a stock 16v (9a) valver, but mine has had a KR Inlet cam fitted, Blitz chip, K&N Panel filter and Powerflow exhaust (with cat fitted) all installed and the car does feel noticeably quicker than it did when standard, but 138.1 BHP sounds a tad low to me, i thought I'd see at least 150+ (??)

 

Vince mentioned that my car was running very lean indeed. He suggsted that the Blitz chip may be causing this and I'll change the chip over and see what difference it makes. However I am not convinced.. (I'm no expert so I'll take Vince's advise before writing his suggestion off) but what I was wondering is

 

1) Does the BHP figure the Rolling Road gave out sound right?

 

2) On the 9A engine (KE Jetronic) does the the ECU control all fuelling?

 

3) Anyone else have lean running C's which were attributed to faulty ECU's?

 

All the sensors on the car are fine, there are no vacum leaks. Vince can sort this problem out for about £250 for a chip re-map, but I'd like to poll you chaps here for any ideas/ comments

[gradeAfailure 0]

1) Wheels or flywheel figure?

2) The 9A's fuelling is mechanically controlled, not electronically...

3) See above...

[chrishill 0]

if vince says its the ECU then I'd listen to the man! ;)

 

138bhp is low considering the mods you've done, if you're really not sure its the ECU you could ask vince to re-test it with a stock ECU and see what power you get before forking out for the remap?

[bcstudent 0]

Wrong. The 9A fueling is mechanical but the enrichment is electronic via an ECU-controlled differential pressure regulator on the side of the fuel distributor. Enrichment on the KR is mechanically controlled via the WUR.

[Blinky16v 0]

gradeAfailure,

Its the flywheel figure that showed the 138.1 (I'd be over the moon if it was at the wheels dude!) :)

 

I thought the KR was mechanical and the 9A was electronic? Not sure Vince would suggest a ECU chip re-map to sort the fuelling if it was mechanical (??)

 

chrishill,

I will shove the old ECU back in and see if it makes any difference. Out of interest does anyone know if there is a Rolling Road in West London ? Stealth is a fair trek for me....

[corradophil 3]

The ECU does control fuelling on Ke-Motronic as fitted to 9As, hence the lambda sensor!

[bcstudent 0]

It's not 100% electronically controlled though. The base fueling is mechanical, only the smaller-scale enrichment is electronic. If you unplug the differential pressure regulator the car will still run (possibly not that well when cold) but there'll be no full throttle enrichment, Lambda control, etc.

[Blinky16v 0]

Phil,

 

Did you see anything similar to me after you fitted your KR inlet cam? It seems odd the car seems quicker now I fitted the KR cam, but the BHP figures are, well pants really.

 

I'm wondering if my car has been running under the stock 136bhp since I bought it.. which is a worry because it beat a bog standard un-modified 9a 16v off the lights and on up to 80 the other day, whereas before I had the mods done it was near enough identical... I'm a little confused by all this an beginning to question the accuracy of the Rolling Road session... arghhhh!!

[bcstudent 0]

What were the exhaust gas readings? How lean was it running?

[Blinky16v 0]

I didn't get the figures off Vince (doh) but he said it was running so lean that it would damage the engine over a period of time if not fixed. Unfortunately the VAG-COM did not work because I think the Bllitz chip have stopped the reading.

 

Running as lean as Vince suggested does logically point to this being the problem with my low BHP. Vince checked the Lamda and other senseors were working fine.... I could give him a call and see if he remembers the figures if you think this will help bud?

[bcstudent 0]

The question was more out of morbid curiosity to be honest. I'm wondering if it was lean only on full throttle though. If so then the differential pressure regulator or the air-flap potentiometer may be worth looking at. I'd start by trying the standard ECU before checking the fuel pressure and the differential pressure regulator loop current.

[davidwort 0]

Hi all,

 

I was up at Stealth on Saturday with Vince. I had my 2.0L 16v C dyno'd and was knocking out 138.1bhp.

 

Sounds fine and dandy for a stock 16v (9a) valver, but mine has had a KR Inlet cam fitted, Blitz chip, K&N Panel filter and Powerflow exhaust (with cat fitted) all installed and the car does feel noticeably quicker than it did when standard, but 138.1 BHP sounds a tad low to me, i thought I'd see at least 150+ (??)

 

Vince mentioned that my car was running very lean indeed. He suggsted that the Blitz chip may be causing this and I'll change the chip over and see what difference it makes. However I am not convinced.. (I'm no expert so I'll take Vince's advise before writing his suggestion off) but what I was wondering is

 

1) Does the BHP figure the Rolling Road gave out sound right?

 

2) On the 9A engine (KE Jetronic) does the the ECU control all fuelling?

 

3) Anyone else have lean running C's which were attributed to faulty ECU's?

 

All the sensors on the car are fine, there are no vacum leaks. Vince can sort this problem out for about £250 for a chip re-map, but I'd like to poll you chaps here for any ideas/ comments

 

you can't expect an off the shelf chip to work properly with an inlet cam from another engine, what engine/spec was the chip programmed for?

a custom remap is the best way to get the most from a specific set-up, then you'll know things are optimised for your own engine.

 

Providing the compression is OK, the injectors and fuel pressure/delivery is OK, you've got decent fuel and the ignition timing is right then I'd expect to see around 150 bhp.

 

The main fuel map on the 9A is determined by the design of the air flap and funnel, the ECU can just tweak things to enable the car to run cleanly for the CAT, but it does give a limited route for re-chipping.

 

Stealth know these cars pretty much as well as anyone, I'd definitely go with their advice, but there's a lot you can do to eliminate problems before paying them to do a final rolling road tune-up.

That chip/ECU seems the most likely suspect to me.

 

David.

[bcstudent 0]

The ECU is capable of altering the fuel enrichment on the 9A injection system by a fair ammount. I'd also be looking at the aftermarket chip as the culprit.

[Blinky16v 0]

bcstudent,

It was running lean all the way through at full throttle.

 

davidwort,

I'll get the old ECU with stock chip plugged back in and see if it makes any difference. I guess if it works I should go quicker! :)

The Blitz Chip was for a 9a 2.0L 16v, although it is pre-programmed not set up specificaly for my car

 

Got plenty to get on with so thank you all for your input :)

 

[Supercharged 2]

Yeah - try the standard chip first - I've never heard of a Blitz chip??

[Blinky16v 0]

You can get Blitz chips off ebay for £50, I was trying it out to see what difference it made... hopefully it is the cause of the problem, but knowing my C it'll be something else uber expensive... gotta love the C!! :)

[Supercharged 2]

You can get Blitz chips off ebay for £50

 

I think we've located the problem then...

[Blinky16v 0]

lol, it doesn't look good for the chip does it... :)

 

Apparently the Blitz chip gives a more "aggresive" fuelling map... I thought this would richen up the mixture. Well no bother, I have a couple of ECU's in my spares box so I'll swap them out and see what happens...

[corradophil 3]

Blinky16v, To answer your question about the KR inlet cam earlier in the thread, at first I really did not notice any change in performance, bit seemed to take a few days, but over that time it appeared to gradually get quicker. There was not a huge difference to be honnest, the main change was that it pulled more vigorously at high revs and will pull hard to the rev limiter.

 

None of the mods I have done have made a anything more than a subtle improvement, but they obviously work considering it made 162 BHP on the rollers.

 

Regarding differences between the read outs, Crazymarcel on here had a lower horsepower figure at the Advantage rolling road day than he had previously got at Stealth, however his quoted torque was slightly higher. Assuming the same differenced apply and stealths rollers read out is still as before, I'd expect to see around 165 peak bhp from mine.

 

If it was me, I would go back to the standard chip, check valve timing and ignition timing and set up the differential regulator current as BC Student suggested.

[Blinky16v 0]

Cheers for the info Phil. I also noticed a gradual increase over time after my KR cam got fitted, very impressed!

 

I'll have that Blitz chip out soon and hopefully that'll release the horsey's !! :)

Just can't get my head around the noticable increase in foot to the floor fun but the low BHP figure... most odd....

[corradophil 3]

bcstudent, You seem pretty knowledgable about KE-Motronic, and yet have an ealier model!

 

I was chatting with Race Power Motorsport, and the bloke there was suggesting you can tweak the fuel pressure to do the equivalent of a WUR mod by removing the differential pressure regulator (If I remember correctly) and removing a screw which then uncovers a grub screw. He suggested a slight adjustment of this may give an increase in performance. I had a little play with it but saw no change, so I put it back to it's original position.

 

Have you ever heard of doing this? Info on tuning this injection is very thin on the ground, but I'l like to understand it better.

[corradophil 3]

Just can't get my head around the noticable increase in foot to the floor fun but the low BHP figure... most odd....

 

Maybe there is another 10-20bhp lurking in there somewhere just waiting to be unleased.

 

If you do put it on the rollers with the standard chip I will be very interested to know how it copes with your setup, if I thought there would be a reasonable gain I'd probably get mine re-mapped.

[dr_mat 0]

Maybe there is another 10-20bhp lurking in there somewhere just waiting to be unleased.

 

I found 17.9 bhp under the rear armrest, where the medical kit was supposed to sit ... :)

[gradeAfailure 0]

Wrong. The 9A fueling is mechanical but the enrichment is electronic via an ECU-controlled differential pressure regulator on the side of the fuel distributor. Enrichment on the KR is mechanically controlled via the WUR.

ah, i see - i stand corrected! that's my one thing learned for today :lol:

[bcstudent 0]

bcstudent, You seem pretty knowledgable about KE-Motronic, and yet have an ealier model!

 

I was chatting with Race Power Motorsport, and the bloke there was suggesting you can tweak the fuel pressure to do the equivalent of a WUR mod by removing the differential pressure regulator (If I remember correctly) and removing a screw which then uncovers a grub screw. He suggested a slight adjustment of this may give an increase in performance. I had a little play with it but saw no change, so I put it back to it's original position.

 

Have you ever heard of doing this? Info on tuning this injection is very thin on the ground, but I'l like to understand it better.

I've spent a fair amount of time reading on the subject and getting dirty under the bonnet of a friend's 9A Corrado. I still don't know that much about it all though.

 

In one respect removing the differential pressure regulator would lose the acceleration enrichment. However, this may be compensated for by adjusting the tamper-proof mixture screw on the fuel distribution head. That screw simply adjusts the height of the control plunger in the fuel distribution head to enrichen/lean the base mixture.

 

I can see that it may well have similar effects to the WUR mod though because, by disconnecting the differential pressure regulator, you prevent the Lambda probe from re-adjusting the richer mixture, giving you the benefits across the entire rev range.

 

If you want to learn about the K-Jet and KE-Motronic systems you could do worse than buying Bosch Fuel Injection and Engine Management by Charles Probst as recommended to me by Gavin (h100vw). It's a very useful book for all 16v Corrado owners.