Another Everest Mountain Chip placed... strange results

[HJ2]

Hi Everyone!

Recently i placed another Everest chip to the car of one of my Belgian friends.
It works and there are no error codes stored, but the behaviour is strange. I thougt to share this and see if anyone else had this experience.

The car boosts quickly and without hesitation to the specified boost (0.96 bar by head)
The car however does not accelerate accordingly.

Up to approx. 3500 rpm everyting is normal, though the spool up time is shorter than stock, as per everest specifications.
After that the pressure goes up like it should but the car does not feel quick anymore (and isnt). @ WOT when boost reaches approx. 0.85 bar you can feel hesitation in accelleration, almost as if the normaly smooth accelleration curve is now 'stepped' and accelleration steps interval-like, almost as if there isn't enough fuel. Sometimes, out of the blue, for a brief moment, accelleration is how it should be There is no turbo pressure variation visible on the gauge at these rare moments.

The car is not nearly as quick as mine and there is definately something wrong, but what could it be?

(new plugs, HT leads and coilpacks installed)

[rip]

Sounds a little like mine before I 'went freelance' with my timing.
I could see the turbo was providing boost because the gauge was telling me so. I couldn't feel it very much though.

Are you also getting excessive overrun popping & sooty exhaust?

[ESM]

Timing is the No.1 thing to check for sure - good power in the mid-range followed by hesitation and poor performance at high boost is typical of the timing being off.

I have also experienced uneven power delivery when the wastegate, while not stuck, was sticky and moving in steps. However, that doesn't explain low power.

Are there any ES logs available? Sensor issues can cause unpredictable problems so it's worth checking they all seem reasonable.

[HJ2]

Thanks, ES log in progress....

[Peter D]

HJ2, thanks for your support !
Hereby the scans, one before the upgrade (07/07) and one just done right now (08/08).
Hope this can help pinpointing the problem.
I had to change the extension ecu to zip, just rename them.

[John_W]

Is the exhaust OK, or has the catalyst broken up causing a blockage? Otherwise timing, plug gaps, then Hall Effect Sensor, coil packs (oops - I see you've changed those) or I suppose injectors could all be things to check.
John

[Peter D]

Exhaust was not O.K., the leak is mended, no change.
Catalyst would not initiate interrupted blockages, it would just generate lots of backpressure in high revs and boost.
The feeling I get is more stepwise full power - slight holding back of power - back to full power - slight holding back of power - ...
Only at maximum boost. Passengers hardly notice, so it's not like fuel cut off or ignition cut...
Plugs where checked only 1.000 Km ago, when we changed the timing belt.

Coil packs are changed to MSD, ignition leads are new Magnecor.
We did this together with placing the chip.
(Back to standard CPU wouldn't bring any information, as the boost would't rise to the troublezone)

I guess I can rule out the injectors, as they would not generate a consequent pattern of 100%->85%->100%->85% engine power.

Maybe some intake manifold sensors giving bad readings to the CPU ?
If anyone can take a look at the Elanscan data, and feedback if they notice something strange ?
I have no clue how to read nor evaluate this data

Thanks in advance for helping out.

[HJ2]

Peter, Did we ever do anything with the Oxygen Sensor?

Elan scan Hero wanted please!

[Peter D]

We didn't, you wanted to order one for me
Looks like you now have a spare one, we could use to test?

[HJ2]

I ruined mine when removing it (tread stripped completely)
The Ebay guy who sold me the new one does not respond to my mails, so better keep an eye on Ebay!

[saska]

Late to the party -- sorry.
These scans look fine with the exception that the car is just not making the power. The ES power is a calculated value but nevertheless gives a reasonable idea as long as the entire logfile isn't uphill/downhill.
- Max power with the Everest was 125 bhp.
Observations that may help you eliminate areas to look at:
- Max boost 0.97 bar
- Timing at idle around 16° BTDC
- Secondary throttle is operating
- EGR valve is operating
- O2 sensor appears to operate normally
- 1 knock event with no timing retard applied -- minor (I'd ignore)
- Air/fuel ratio 14.7 except under high boost when it drops as per normal
- Coolant and MAT values look fine
I then looked at some individual events more carefully so all of the graphs below have in common:
1. WOT (wide open throttle) as reported by ES
2. 3rd gear only acceleration runs
3. The graphs are 6-7 seconds long
The first graph is with Everest chip and shows left Y-axis as Boost (Solid line), right Y-Axis as RPM (Hashed line) and X-Axis as Time in secs.
Here you can clearly see the RPMs falling back, along with a quite marked variation in boost.


The next graph is the same event (Everest run) with right Y-Axis as Power
This quite clearly shows a substantial variation in power


So to try to see if it was the Everest chip I looked for a similar event with the std chip ES.
The graph below is with std 1499 chip and clearly shows the engine RPM dropping back and the variations in boost. The RPM dropback is much less than on the Everest run and was probably hardly noticeable in driving but nevertheless it is there so logic suggests it is something to do with the car and not the Everest chip.


So what might be causing all this ? The speculation below is worth what you're paying for it:
1. Always worthwhile to check both ends of the engine earth which connects to intake manifold at timing belt end (beneath lifting eye) since all the engine sensors ground via this.
2. Is it possible one or other of the cams is a tooth out from changing the cambelt ? No offence -- I'm just asking.
3. It is possible one or more of the fuel injectors can't keep up but that doesn't make sense since even with the Everest they're only at max doing 80% Duty cycle.
4. A boost leak is possible so see the excellent WIKI for JonT's method.
5. My real gut instinct is the same as John_W's -- blockage in either precat or exhaust.
Reasons:
- Grandad who builds model aircraft engines and exhausts from bare metal says exhaust condition and design affects power enormously.
- In the graphs the boost is building to max, dropping back, building again, and so on. Exhaust blockage in a normal car reduces power but in a turbo car may also "stall" the turbo which then takes time to spin back up and also to build the pressure in the intake manifold which appears to be what we're seeing.
- There are 0 instances of overboost which one would expect with sticky wastegate, duff boost control valve, so it appears something else is causing the boost falling back.
- In the Std 1499 graph you can clearly see the boost is taking longer to recover as the revs rise.
- Elanscan stops at the O2 sensor so doesn't know what's going on in the exhaust or how fast the turbo is spinning. All ES is telling us is that this is happening but all the rest of the readings look normal to me so it is probably something ES can't see. 2p

[HJ2]

Hi Tony!

Wow,
Really, really appreciated!
A great reply cries for a complete answer. I'll have some spare time tomorrow!



Henk-Jan

[norman lovie]

is the clutch slipping ?

[Peter D]

Thanks for looking into the ES data, and your input.
I'm offfor a business trip in 7 hours, only returning this weekend.
I'll get in touch with HJ2 to start on looking in to possible solutions step by step.

I don't believe the clutch is slipping, it would start to smell pretty bad...

[HJ2]

Hi All!


Finaly found some time to respond.
I drove a while behind Peter last sunday during the Belgian 'Lotus Summers End'. We were not exactly driving slow
in 1st and 2nd gear there was virtualy no difference between our cars. At the end of the 3rd gear mine was running a bit faster though. This is the same point where the 'stepped'behaviour of the boost begins (Right, Peter?).
I did not smell a slipping clutch and this would definately have been noticable in performance.

On his way home, after driving for a while after slow traffic, boostcreep occured (1st time!) @ WOT.. Perhaps this helps pinpointing the problem. I now believe that perhaps the wastegate is seized or the flap is sticky at the last 5% or so. This would be easy to check! Hwever, with boostcreep one exects excess power, not reduced power ...

The graphs as above are exactly in the problem zone, good deduction dear Watson! (Ehrmm.. i mean Saska)
The variation in power (2nd graph) is not only good visible but also good noticable in the car indeed.

Troubleshooting steps:
1. Good suggestion! Will do that when the car is here.
2. It is possible that the timing is one tooth out. However it is very, very unlikely and a lot of work to check. Could this cause the symptoms Peter is Experiencing?
3. OK
4. We'll check for boost leaks and i will get me a ring beard
5. Blockage of cat is supposed to be tested by the dealer. I however agree with you that this is still higly suspicious and this was my initial thought as well...


We're zooming in now! thanks for all the help

[Peter D]

It is the same point where the 'stepped'behaviour of the boost begins.
Though don't pay too much attention to the 120 bhp on the graphics. You would have been able to overtake me anytime, in any gear

I guess there is no easy way to find out if there is a blockage in the precat ?
Timing belt would be surprising, as we both doublechecked before putting everything back.
And the engine runs very smooth on idle. But you never know...
Let's start with the things that are easy to check, mostly it's simple things giving you a hard time

By the way, the engine stall resulted in an engine error, code 31, overboost. (Boostcreep ?)
Don't the injectors stop working at some pressure level ?
Let's start with the wastegate and the electrical ground connections...

HJ2, Send me some dates you could free up some time so we can look into this (and install the shortshifter and gear cables).
Now time for

[ESM]

The logs look ok to me for the most part. However, one anomaly is the noise on the engine speed data. Usually this is pretty smooth data - unlike the road speed input which can be pretty wobbly. I would suggest there might be a CAS issue, coil baseplate fault, or a wiring/earthing problem related to those circuits. I doubt the drops in rpm indicated in the, very useful, traces saska posted up are real... A drop in power is one thing an actual deceleration is another.

A comparison of a random bit of engine speed data from this car and one of mine is shown below...

noisyrpm.JPG

The difference is the s/n ratio across all engine conditions supports the theory a problem might be found here

I have a coil baseplate I could lend you (somewhere) if you want to try substituting that. The most likely culprit, for my money, is the CAS.

Rest assured if you can't get the chip to work with your car I will give you your money back regardless of where the problem lies.

[HJ2]

Thanks for joining the discussion 'ESM'
The s/n ratio is a tad strange indeed and does match bad ground connections mentioned earlier in the thread. This is definitely something we need to to check first Peter!
Good you have a spare CAS we can try as well.

To be continued

[ESM]

Sorry I've no spare CAS - just a spare coil baseplate (it houses electronics related to CAS and ignition function).

[HJ2]

Ah, sorry, I meant that Peter has one (it is in my garage
However... no spare baseplate, so I might come back on that one