About To Have A Bonfire With My Car

[brozilla]

Greeting everyone. I haven't posted here in some time because my car has been running well but recently I have hit a wall trying to troubleshoot a problem.

The car won't rev past 3k, it falters up to 3k then surges and pops and bangs and might get to 4 before it just has enough. I'm not getting any codes. It isn't running rich or lean. I just have no idea. I'm thinking vacuum but I went around the motor pulling lines while she was running and I couldn't find a culprit. I've never had this issue before, even when my of my header bolts came loose on the block it still reved to redline, it just ran like crap in low rpm's.

It is undrivable, it bucks like I'm slipping the clutch when you're just trying to go over 20mph. Any thoughts? The idea of lighting this piece on fire and shoving it off a cliff sounds better everyday. Its a 4.6 with PI swap and literally every bolt on you can do. Thanks!

 

[wmburns]

Has the battery been tested? Does it hold a charge?

Are the battery terminals clean and tight?

Has the alternator been tested for correct output and/or excessive AC ripple (bad diode)?

What's one possible cause for bucking..... A cam sensor related problem. What's one possible cause for a cam "issue"? How about excessive AC ripple. Are you seeing a connection here?

Does the motor make good power below 3K?

Has the fuel pressure been tested? Is the fuel pressure intake vacuum reference line connected and leak free (since I don't know the model year of your car I don't know if this is a return or return-less system).

Manual or automatic?

Does the speedometer work and is it accurate?

Any DTC codes?

 

[brozilla]

Has the battery been tested? Does it hold a charge?

Are the battery terminals clean and tight?

Has the alternator been tested for correct output and/or excessive AC ripple (bad diode)?

What's one possible cause for bucking..... A cam sensor related problem. What's one possible cause for a cam "issue"? How about excessive AC ripple. Are you seeing a connection here?

Does the motor make good power below 3K?

Has the fuel pressure been tested? Is the fuel pressure intake vacuum reference line connected and leak free (since I don't know the model year of your car I don't know if this is a return or return-less system).

Manual or automatic?

Does the speedometer work and is it accurate?

Any DTC codes?

The only DTCs are p1000 OBD system check not complete, and another one for evap.

Battery is brand new, terminals are clean.

I don't know how to test Alt, can't drive the car to autozone.

cam sensor is new, wiring harness is new-ish.

new fuel rails put on with good pressure, fuel filter could possibly be needing a replace.

T45 manual.

Speedo is not accurate, its 15 low.

 

[wmburns]

ForScan ODB2 scanner w ELM327 USB

Do you have a Windows laptop? Do you have $30? If so consider getting the ForScan ODB2 software based scanner. This is a very powerful ODB2 scanner that has to be seen to believed especially considering the low price ($30). The data logging capabilities are nothing short of amazing. A complete game changer. However expect a steep learning curve with the tool.

OHP Ford ELMconfig USB device 500kbit/s ELM327 compatible interface with MS-CAN switch for Forscan FoCCCus Mazda OBD2 diagnostics

ForScan.org home page

 

[brozilla]

ForScan ODB2 scanner w ELM327 USB

Do you have a Windows laptop? Do you have $30? If so consider getting the ForScan ODB2 software based scanner. This is a very powerful ODB2 scanner that has to be seen to believed especially considering the low price ($30). The data logging capabilities are nothing short of amazing. A complete game changer. However expect a steep learning curve with the tool.

OHP Ford ELMconfig USB device 500kbit/s ELM327 compatible interface with MS-CAN switch for Forscan FoCCCus Mazda OBD2 diagnostics

ForScan.org home page

This is amazing, thank you.

 

[brozilla]

Update: Today I continued to trouble shoot and I was going to data log it with my X3 when I got a p1444 evap emission system purge flow sensor circuit low. I'm thinking this could be my issue, but where is the purge flow sensor?

 

[wmburns]

If by chance this is a 1996-1998 model year, the Purge flow sensor is located inside the engine bay. It's mounted in the EVAP line between the throttle body and the right hand fender well. Fuel vapors are hard on rubber/electrical parts. As such the PF sensor does fail at a high rate. The part is cheap enough to replace for pure diagnostic reasons.

 

[brozilla]

Thanks wmburns, I found 2 canister looking things between the passenger fender well and throttle body. One sits low by the AC and one is higher about 16" from the back of the throttle body. I'll try to upload pics, but neither of what I found looks anything like the haynes manual and it is a 97 gt

 

[wmburns]

Here's an example of the purge flow sensor. Follow the EVAP line along the cowling in the engine bay. If my memory is correct it's routed along with other vacuum lines running along the cowl ending in the right hand fender well.

The really LARGE canister thing is likely part of the AC.

For the 1996-1998 model year Mustang the EVAP charcoal canister is located inside the passenger (right hand) fender well.

The EVAP solenoid is slightly larger than the PF sensor located along the same EVAP vacuum line. It does look like a cylinder.

http://www.rockauto.com/en/moreinfo.php?pk=1191644&cc=1134234&jsn=581

NOTE: IMO a bad PF sensor itself isn't likely to cause the symptoms reported. IMO it's more likely to have a stuck open EVAP solenoid allowing unmetered air to enter. The EVAP solenoid is easily functional tested. You should not be able to blow through it with no power. Once power is applied you should hear the click and be able to blow through it.

While there check to see if the EVAP line is actually connected to the charcoal canister.

 

[Neuron]

ForScan ODB2 scanner w ELM327 USB

Do you have a Windows laptop? Do you have $30? If so consider getting the ForScan ODB2 software based scanner. This is a very powerful ODB2 scanner that has to be seen to believed especially considering the low price ($30). The data logging capabilities are nothing short of amazing. A complete game changer. However expect a steep learning curve with the tool.

OHP Ford ELMconfig USB device 500kbit/s ELM327 compatible interface with MS-CAN switch for Forscan FoCCCus Mazda OBD2 diagnostics

ForScan.org home page

Would this access codes for the traction control/ABS? Was told by numerous Scanner Tech lines I would have to get a professional grade(expensive!) tool that lets you input specific information about the car ie Model Make Year etc. Had an OP try with his cell phone app. but still could not access the code(s) to find the problem.
Thanks and sorry for the off subject post.

 

[wmburns]

Would this access codes for the traction control/ABS? Was told by numerous Scanner Tech lines I would have to get a professional grade(expensive!) tool that lets you input specific information about the car ie Model Make Year etc.

Yes ForScan does read/access the "other" modules including ABS.

ForScan does have a limited number of "two way" tests. I have used to cooling fan hi/low tests on my Wife's Town Car so I know they work at some level.

Plus wait. There's more....

For a small addition fee you can get the extended license which will allow for PATS key reprogramming. Which would also be handy if replacing cluster and other body control modules.

http://forscan.org/forum/viewtopic.php?f=5&t=836

I have been testing the ForScan and the AutoEnginuity products. IMO the graphing is superior in the ForScan. The two way tests and manufacturer support is far superior in AE.

BUT....... ForScan has a huge price advantage over AE. At only $30 the product is a game changer if it only included the graphing functions.

Finally I paid the greater price for AE because I work on more than Fords. In that way the AE support of multiple car manufacturers makes it worth the $$'s (for me).