runs with stock ecm, not with xfi 2.0

DGC

Senior Member
Joined
Jan 10, 2004
Back again with yet another 'will not run' issue. 87 turbo that has been in continuous mods since purchased over 2 decades ago. Current condition has engine running with stock ecm, but not with xfi. Most recent mod was a complete capar's wiring harness. Nostart tree checks find 1) fuel fine, 2) spark fine 3) ccci fine, checked with caspar's tool, 4) timing fine, again caspar's tool. Lights on xfi box indicate proper cam and crank signals. Caspar's ecu box sent to Caspar's and checked fine. Xfi unit sent to comp and checked fine.

My guess is that there is something in the xfi communication that is not correct. Connection to xfi is confirmed. VE tables display as expected. Cranking gives appropriate signnames (rpm, tps, etc.). Loaded most recent tune from Anderson's, w/r any change. Went back to the xfi manual looking for anything I should be checking.

There should be something buried in the xfi unit that I should be able to display via my computer. Comp folks have not been overly helpful.

If anyone has a suggestion about using the xfi unit to debug this issue, please comment.

FYI, the xfi unit has not been reliable since installation in 2005. Seriously regret the purchase. But that's in the past... Task now is to get the engine running. I would add that Anderson's have been my choice for working on this car. In fact the xfi was purchased and installed by Bill. Unfortunately, the last time this happened (2020), Anderson's was able to fix it. But no explanation was provided when the invoice ($$$) was paid. Nothing against Bill. He knows this car better than most. Keeping it running has become a serious issue. I should be able to diagnosis this hale without expecting a $$ service charge everytime this happens.

Thanks,
DGC
 
Post the tune and do a short data log of an attempted start.
Put them in a zip file.
Link up, start log, then attempt a start. Just a few seconds should suffice.
 
Thanks Chuck,

Please check attached log. I used a nearly complete dash. If i left something out, please let me know. Or if I screwed up the log, let me know as well.
I should add that with ignition, the engine fires, then dies. With stock ecm, it will fire and run.

Please let me know what you find.

DGC
 

Attachments

  • temp.zip
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Forgot my tune.
 

Attachments

  • 300sc96inj_copy_mem_day_mod1.zip
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I should add that with ignition, the engine fires, then dies. With stock ecm, it will fire and run.
You have the rpm cut set to 50.
From the basic setup info: "
6.2.2 Spark Cut Rev. Limit
This is an ignition rev limiter used for maximum RPM rev limiting. It is always active. If this feature is not to be used, enter a RPM value above what you will ever reach.
Goto: System config, then to global set up and take a look.
1 other comment: Your timing map takes a serious drop of pulling 10* all at once, at 3000 rpm.
It may be a bit smoother to blend the cells more instead of a 10* hit at one time.
Have you had it on a dyno?
If so, where's peak torque?
What does a set of new plugs with clean break look like?

It's been a while but what's going on with the crazy individual cyl fuel correction?
Is that from the learn results?
The timing individual is all at 0.
 
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You have the rpm cut set to 50.
From the basic setup info: "
6.2.2 Spark Cut Rev. Limit
This is an ignition rev limiter used for maximum RPM rev limiting. It is always active. If this feature is not to be used, enter a RPM value above what you will ever reach.
Goto: System config, then to global set up and take a look.
1 other comment: Your timing map takes a serious drop of pulling 10* all at once, at 3000 rpm.
It may be a bit smoother to blend the cells more instead of a 10* hit at one time.
Have you had it on a dyno?
If so, where's peak torque?
What does a set of new plugs with clean break look like?

It's been a while but what's going on with the crazy individual cyl fuel correction?
Is that from the learn results?
The timing individual is all at 0.
what version are you using to read the file
op said he has 2.0 .. looks fine on ccomWP 2.01
2.05 is a different animal and would need many tweaks to the file to be able to run a 2.01 file .. they are not interchangeable
 
Thanks Again.

Carefully scaned my XFI manual and will need more details. My manual has 6.2.2 Ignition Type, not
Spark Cut Rev. Limit. When I go to Operational Parameters, I am not finding anything with the value of 50.
Is it possible my Manual (dated 2012) is not correct?

On your second point, I do not know where the factor of 10 for scaling on my timing map is found, either under the ccomp utility or in their manual. I agree that a scale factor of 10 at 3000 rpm seems abrupt, and would like to know where to make/find this adjustment?

As I noted everything has been done by Anderson Performance. My most recent visit ($$$) had the injectors replaced (apparently #6 was continuously on), new plugs and the oil changed. Car was trailered back to my house, parked and then covid changed priorities away from the buick. Now I am picking up things again, so no miles are on the car since Anderson's.

The car has been dynoed by Anderson's two times (not sure why another dyno was needed!!!). All I was given was a printout showing a linear rear wheel hp that peaked at 510 rwhp for both dynos. Can't answer where max torque occurs. I am pretty sure the dyno results were not logged!!!

I will go to the comp web-site and see what I find with updated manuals. Is there a possibility that a different software version was installed when Comp checked out my xfi??

Again, thanks for your help. I admit my learning curve has some gaps, but getting up to speed will happen.

DGC
 
PACECARTA,

Thanks. 2.01 versus 2.05?? How do I check this out?? Does this mean Comp's operating system or something else? It is possible that Comp installed 2.05 when they checked out my unit. Is there a way to get back to 2.01??

More to learn..

DGC
 
if i open the file you posted with ccomWP2.051 the individual cyl table has crazy values leading me to believe its not a 2.05 setup tune
if you have 2.05 theres a checklist of things that have to be checked to use an earier GCT file , but for one youd need to zero out that indiv cyl table table

i also see in op params the oil cut is enabled (checked) and set at 8psi , if you arent running an oil pressure sensor on aux2 input the car wont run until that box is unchecked
 
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PACECARTA,

Humm!! Since the xfi is from 2005 (??) it must be 2.01. I will check tomorrow. I found a file named ccwpxfi20109B in my downloads. My guess is that my xfi was flashed with 2.05 when Comp checked
my unit out??
When I connect to my xfi tomorrow, if I find it is 2.05, would you recommend following 26.3 Flashing the update into your ECU? Instructions say to ground blue wire in pin A of the DIAG connector or pin A21 of the ECU.
Might be easiest to ground A21 from backside of the connector. Any harm in grounding with connectors all plugged in?

DGC
 
if you have 2.05 flashed to your ecu , you need to use 2.05 software to properly view or save the ecu GCT

if your program is older 2.0 version and your ecu is now 2.05 you need to go through th tables and points in the checklist file included here
 

Attachments

  • XFI 2.010 to 2.050 update notes 2.pdf
    171.1 KB · Views: 27
if i open the file you posted with ccomWP2.051 the individual cyl table has crazy values leading me to believe its not a 2.05 setup tune
Mine is 2.051.
Probably should disregard what I've posted.
 
PACECARTA,

Thanks again. Before taking these steps, it also seems logical to reflash my unit to 2.010 (following the instructions in section 26 of the manual). However, when following these steps the flash ecu option in greyed out. Would you think the a call to Comp would be helpful for getting my unit reflashed to 2.010? My guess is that they would request another return???

Having said this, I will attempt to execute the steps in the shared pdf file.

DGC
 
PACECARTA,

Looks like there are software issues that need to be sorted out. My CComWP software indicates version 2.051.
However when I attempt to execute your pdf instructions, I get:
Step 1) under 'spark functions' I do not have 'Spark Offset vs FEC. Only Spark Offset ATS and CTS.
Step 2) No individual cyl fuel table. Only cyl enrichment and timing retard settings
Step 3) No 'Spark Cut Rev Limit'
Step 4) No 'ign Parameters'.

Fished at fuealairspark.com and installed another version of CComWP, with a different front page. Unfortunately ECU not found prevented further investigation. I tried all 4 com ports w/o success. I recall that there were specific serial cables needed for this connection. When running my original CComWL version, connection is not a problem.

Software version, tune tables (2.010 to 2.050 or vice versa) and serial cabling are not yet resolved.
Not really sure how to proceed. Weekday contacts with comp are not an option.

DGC
 
Thanks to all. Sent xfi back to comp. Will let you know what happens.

DGC
 
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