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Ford mustang elite 2500 dbw throttle doesn't match pedal when engine on.

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Not sure if this is the right location. and this may take a few posts to really narrow in on where the issue is. I have a '14 Ford Mustang that is swapped with a built out Ford 3.5l Ecoboost short block. the Heads are mostly built Ford 3.7l from the OEM motor. running a P1SC procharger. combo drove fine on stock pcm but wanted more functionality. Finished wiring in an Elite 2500, swapped engine over to a map sensor from MAF. have the ecu configured for the car. worked with Haltech and have the crank & home signal locked in. TDC offset is all done with a timing gun - get full sync from the haltech. Car runs and idles once its warmed up a bit and was working through the next section of practical stand alone. solved some wiring teething issues related to ignition and fuel injectors. came back to the base fueling. I can bump the idle rpm up so I know the ecu has good command over the throttle body.

current issue is that when throttle pedal is applied the throttle body doesn't track with it (it does when engine off) and the load wanders all over the fuel map. this prevents the engine from reving over 1500. Where does one start on ruling out issues so that the car can be driven. I played with the logging feature a bit in the ECU but it's completely different than HPtuners so would need some pointers on making a log file to attach to show the issue. Again, running on all 6 and at idle I can get the lambda to match target on both banks. just won't rev.

Thanks in advance,


Bump. verified a few things today. fuel pressure is steady while depressing the throttle and if pressed far enough it will jump up and run smooth about 2K rpms. looking for new ideas to try and feedback on providing logs for review.

Perhaps settings related to idle control need adjusting. Look for parameters related to Pedal Position to enter / leave idle control.

In Setup->Main Setup->Engine what is Throttle Limits -> User Demand Minimum? Does the throttle pedal go above that before the engine jumps to 2k RPM?

Do you have the DBW Brake Pedal Check enabled? Is the Brake on? What is the Max Braking TPS?

I see in the Haltech help, reference to a Throttle Follower table? Do you have that? That looks like the area that might need adjusting.

That makes sense with what I feel. as I raise the throttle the system then bounces between the idle control system and the non idle throttle pedal system which feels like the car is "hunting" and the load wanders as it tries to blend the two outputs.

I'll start with the idle control enter/exit threshold and report back soon.

I have the DBW brake pedal check off as that trigger just recently got wired in to the pedal and validated it was triggering correctly. This will be the 2nd avenue once exhausted the idle control threshold.

You might want to try raising the Setup->Main Setup Functions->Idle Control->DBW Max Position. It seem like this could possibly hold the throttle back as it tries to blend into normal operation.

I would suspect a wiring and/or connector problem - it is possible for the running engine's movement to cause an intermittent OC/CC condition that could cause a lot of random scatter?

Gord, haven't ruled out a mechanical issue yet.. tho its low on the risk level. the harness is a haltech plug & play for a coyote 5.0 that was pared down two cylinders as far as ignition, throttle & fuel injectors are concerned. a lot of effort went into the crank and sync wires with Haltech support since this is an oddball engine for them. ECU reports back full sync even when its having the issue. but keeping an eye on them.

made a little progress on finding what all is of note when adding throttle to get to 2000 rpms. there's a 40% disparity between bank one & two. which based on getting it to idle means one cylinder isn't happy. either no spark or no injector. for confirmation dialed in each cylinder of bank two lean by 40% and it started behaving. obviously thats not a fix. it proves that fuel is the issue on a cylinder. had to run some errands. came back & fired it up and at idle it is now being rough. thermal gun says cyl 1 needs some attention so waiting for the engine to cool to get under the intake and see what's what. trying to figure out how to be under the hood checking items. probably going to stretch the cables so the pedal can be on a mobile plate so I can rev engine while aiming the thermal gun.

update. all of the spark plugs are showing signs of carbon/fuel rich. going to swap out for new ones and observe o2 readings. engine was idling a while with rough base fuel during troubleshooting ignition and fuel glitches. see if new plugs running on all 6 gets a better out put to dial in fuel table.

Any chance the wiring / firing order isn't correct? Do you have a feature to check ignition & injection on individual cylinders? Also does it correctly identify when cylinders are in which bank.

wiring is good. runs on all 6 based on IR thermostat. each runner at the heads have equal temp after replaced plugs. a few were fuel fouled from the wiring teething. tried reving again and it runs into a dead spot for a bit (sputters, flutters) after which it spikes and holds ~2k, then can follow above that. looked through all of the idle control settings. nothing jumps out as "idle control is less than this, throttle control is above this". looked in DBW and everything there was about controlling the throttle closure from transients. looked at the fuel tab and the idle tab. nothing in there about separating idle control from throttle control.

It would be really handy to know how to provide a log so people can view what's going on. is there a elite 2500 expert that can walk me through this?

Hi Matt, that sounds like a weird issue you've got. I'll add a couple of points to the thread. Firstly the relationship between TPS and APP is not necessarily 1:1 and in fact usually you wouldn't want that. In the DBW setup function under 'Main Setup' you'll find a calibration tab and at the bottom there is a graph of the TPS/APP relationship. You can manipulate this by dragging around the little points on the graph. Secondly you can log in two ways - When the laptop is connected you can log to the laptop by going to the 'data manager' tab at the bottom of the ESP software and start recording. You can also stop and then save from there. This is relatively low frequency data but should be more than sufficient for your issues. Alternatively you can setup onboard logging from the "Datalog' tab in the 'Main Setup' menu. You'll need to define logging conditions (rpm >500 will suffice for now) and add each channel you're interested in and set the frequency.

here's a brief simple log of the issue. 11 channels guessing they'll be helpful, it behaved a bit differently but you can see in the trace it goes haywire.. can the elite 2500 build some histograms like in HPtuners so that the data can be studied? Tried to post the tune file but the forum file system doesn't like the 2500 file type.

Attached Files

Looks like Bank2 has some serious mis-fires going on. Several lean spikes that coincide with RPM drops. It happens as soon as you provide more air by opening the throttle. You said the ECU has good control of the throttle, what happens if you just raise the idle in 200 RPM steps from 1000 to 2000 RPM. will the engine run steady -- can you tune the fuel in those cells.

Bank 1 is as much as 10% lean while at 1000 RPM, idle control is having to add timing to keep the RPMs up. Why the difference between banks?

Any chance of a mechanical issue in the intake manifold (did you leave a rag in there?)

Put your calibration files into a ZIP file then you can upload them.

I would love to learn more about how to read all that looking at the log. elite2500 I see the traces but it's not labeled what each is and its so small at the bottom of the screen. surely the elite 2500 has the ability to parse all that like hptuners into a larger display with labels?

I've rerun the log I made yesterday without any cylinder offset so it shows 20% offset, I had some baked in for a test and wanted to show it without. so this log and file are as best I understand from following the practical stand alone up through module step 6 of the elite 2500. I watched all of the general course work through the certification page and understand that.

things I've tried. verified that the wiring is physically good to each cylinder. the bulk of it is in the haltech loom because it's a plug/play harness.

verified that the injectors are seated and no leaks on bank 1 & 2 while the intake was off. intake is back on which blocks bank 1 so hard to test that bank while engine is running.

verified tdc offset is correct at idle. haven't been able to retest at 2k rpms like in course because it won't hold it yet.

Attached Files

Looking at your configuration, I noticed you've set the Throttle Limits (User Demand Minimum to 10%) -- I think you want to make this like 1%, so the throttle is responsive from when you first move the pedal. This is on the Setup->Main Setup / Engine Main Page. See attached picture.

I will make a video showing you how I look at your CSV logs using Megalog Viewer...

Attached Files

made a ton of progress on it tonight. the other trending topic on cop dwell vs tdc offset made a lot of sense for this. there's no way to get a lead on the #1 plug, it's under the intake. so tdc offset was using the coil lead on #4 that I can reach. I dialed the tdc offset back 4 degress and it revs now. moving the min throttle to 1% improved the response. What is a HT extension? where do I get one? I have room to set the coil to the side and snake an extension under the intake to redo tdc offset using #4, I made marks on the timing cover and balancer for it. but it makes perfect sense why it was just on the verge of misfire as rpm increased.

here's latest file and log.

Attached Files

I like the extension lead from Pico Automotive -- buy from Autonerdz, the best Picoscope dealer in the US.

I think you may be making a common tuning mistake. You need to make sure the engine is in the fully warmed up state (70-90 degC, 160-195 degF). You aren't logging ECT (Engine Coolant Temp), but the Idle Target RPM gives me a clue, since it's 1400 RPM. Looking at your fuel table, I notice that as the Manifold Pressure increases from your idle, you don't always have more fuel, so it tends to go lean as you open the throttle and increase the MAP.

I suggest this process -- let the car idle to get warm. Then change the Idle Control Target RPM in steps to match your fuel table (so 900, 1100, 1200, 1500) and tune the fuel for each of those idle conditions until your WB02 matches your target. Make sure the fuel table has larger values for increased MAP values above these idle conditions for the same RPM.

Set the Idle Control Target RPM back to 900, now do your test with moving the pedal slowly (to avoid transients), and holding it at various RPMs and MAP. Adjust the fuel in those conditions. Smooth / Adjust your fuel table following those trends.

those tips match what was in the practical stand alone & I do this when working with HPtuners. Appreciate hearing the consistent feedback. for the purpose of solving the rev issue where the warmth of the engine didn't change the result, these tests were run from cold start, turn off after a minute of test and restart after changing values, rinse repeat. since it was unsure why it was fouling plugs.

Going to close this topic as resolved. with the HT extension from pico the timing was only 1* off from predicted based on discussion. engine has a smooth rev as pedal is applied now that TDC offset was measured from spark lead instead of the coil lead.