VE table shows no psi.

[Spud]

Been a while since I've posted. My car has been in cold storage for the winter, but I'm working on getting it ready for Spring. I have a Cobra TT and I have a 2001 version of the FAST ECU, and was wondering if there was something wrong with my box? I went to start up my car the other day and it ran like crap where I had started it up on several prior occasions and it ran great. This time I started it, I couldn't get it to hold an idle until I changed the throttle body and changed the cells on my VE table richer. I Opened the VE table while running, and the "cell" was pegged showing no psi, rather it only moved from left to right as RPM was increased but no vertical movement to show increasing psi. My boost guage was showing some activity, but never showed on the positive psi side and I revved it pretty good. Just stayed in the vac range -2 to -20psi vac. I'm figuring it has to be the leak I found at the MAP sensor??? My boost controller is T-ed into the same line as the MAP.

To test the MAP sensor I put the ignition hot and without the car running opened the VE table and put an air hose to the MAP to apply some psi to see if the ECU read it. Without hardly any psi, I felt air blowing pretty good from the MAP sensor, but it showed some reading on the VE table cell so the ECU was at least reading the MAP.

I have a Greddy electronic boost controller and if that wasn't seeing any boost because of the leak, then that may explain why I couldn't hear or feel the turbos kicking in when I revved it..? Is that normal for a MAP sensor to just pop a seal or blow like that? I tested a spare 2 bar MAP the same way and it didn't have blow-by like the 3 bar. Any other suggestions besides the MAP as to why the VE cell flatlined and won't read positive psi?

Thanks,

Spud

 

[HighPSI]

You need to have a dedicated line going to the MAP sensor. If air is leaking out of the sensor it's probably bad. Is it stuck at 0 kpa or 100 kpa? Do you have MAP kpa in the dashboard at the bottom of the screen?

 

[Spud]

The line going to the MAP sensor is T-ed with the FPR and goes right to the intake from that, but the line to the MAP is not dedicated. I do show Kpa on the dashboard as well but when idling it's a big red zero (0). I stopped by the local GM dealer today and ordered a new 3 bar MAP sensor and so I'll be able to pick it up tomorrow. I put a vac line to the 2 bar MAP to test it and it held pressure just fine, but the 3 bar one I suspect is pooched didn't hold pressure at all and readily leaked out around the edges of the flat side you plug the vac line into. So, in your opinion I should dedicate a line and try a new MAP sensor..? I'll do that as well and rearrange the vacuum lines when I get the new MAP to try tomorrow or Friday..?

Thanks for the advice.

 

[HighPSI]

So, in your opinion I should dedicate a line and try a new MAP sensor..?

That's what I would do. The dedicated line isn't a "must" just a matter of preferance

 

[Spud]

I've got my replacement MAP sensor and plan on rerouting the vac tubes to dedicate a separate line for the MAP. Word is you know your sh*%... I won't be able to see if the replacement MAP solves my problem though until Friday sometime...

If it's an ECU problem I may be giving you a call. I'm still not there for going to an XFI but I'm not too far off..?

Thanks,

Steve
aka Spud

 

[HighPSI]

I will be in Gainesville all weekend. Call 321-722-1563 and give Holly a message if you need me.

 

[Spud]

I was able to try my new MAP sensor and absolutely no difference in the reading on the VE tables. The cell that I'm used to seeing at least one or two spots up from the bottom of the table when idling and then bumping up 4 or 5 high when pumping the pedal to about 3,000+ RPM, lays FLAT on the bottom of the table as though there was no reading from the MAP at all. However, I do see that there is some MAP activity on the bottom of the screen, just nothing in the positive psi category. I also tried bypassing the boost controller thinking maybe that was not functioning, as it seemed like I was getting no boost at all, and there was no difference at all in the readings. Any thoughts as to what I should check? Maybe it is the ECU that's acting up? Again, this just came out of nowhere where I've been just starting my car up every other weekend for the past number of months without issue. Just this last time when I started it the VE table was flat...

Let me know what you think?

 

[BigBird R/T]

Spud, did you ever find out what the problem was with your VE table reading?
The reason I ask is because I have the exact thing happening but in the Base Spark Table.

Thanks,
Ron

 

[HighPSI]

I too am curious about Spud. I never got a phone call so ASSumed he was fixed.

Make sure you have MAP kpa in the dashboard at the bottom of the screen. If you have an XFI, go to View/System Config/Sensor Calibration/Map Sensor and verify the table is correct along with the MAP voltage.

 

[BigBird R/T]

Cal, I have the C-COM WP and do have the MAP kpa loaded in the dashboard. The MAP kpa shows correct numerical numbers in the dashboard but the bubble only floats left to right on the bottom line. VE and A/F screens work fine. Any ideas?

 

[HighPSI]

Since yours shows the correct MAP in the dashboard, it's probably a software issue. Try reloading the software or borrowing someone elses laptop.

 

[Spud]

Sorry I was outta the loop for a few days (visiting family in Utah). I just finally was able to try a couple of things on my end today including making sure the MAP Kpa was in the dash. When I checked my main dash it was missing MAP KPa and so I added that back in. Don't know how or why it was taken out, but whateva... Anyhow, running the car after that didn't fetch any different results. The bubble in the VE table still only moved left to right, but not vertically, but the KPa was showing in the dash below just fine and revving it to 3,000 rpm showed between 20 and 65 KPa. However, the bubble stayed at ground zero like it was weighed down by a rock. All connections to the NEW Map sensor and all other lines look good. Also, the continuity of the wires from the MAP connector to the pinout at the ECU is also good. I just now removed CCom WP from my laptop and reinstalled it, and so I'll try that tomorrow and see if that's what's up. I also have a secondary laptop to try.

I won't have a chance to give this some concerted effort or time until probably the week's end. I will post my solution, and if I don't solve it on my own I will give Cal a call from Hartline to see if he has any suggestions. Thanks for extending the invite to call and ask Cal. If I run into a brick wall I will call...

Either way I'll post the results, as I see I'm not alone with this problem. Incidentally, I e-mailed my contact at FAST and he replied with a very similar suggestion as above noted and that is make sure the MAP Kpa is in the dash and if that doesn't work, then reinstall the Ccom software...

I'll post results.

Spud

 

[Spud]

As per Cal from Hartline's advice, I first tried adding back in the MAP Kpa into the main dash to see if that breathed some life in the VE cell (vertically) and that did not work. I then took the next step and uninstalled Ccom-WP from my laptop and reinstalled it. I then first thing this morning I went and plugged in and started my car, and guess what... It now works!

Thanks again for the help...

Question: Would the .gct file that I've had when my unit was B2B work similarly on the ECU switched to SEFI? It didn't appear to be even close from my trial and error. I had to re-do almost the entire VE table, with the balance being more or less similar (MAP AE, idle settings, temp AE etc.)...

Regards,

Spud