[rusEfi] 2003 Dodge Neon (#9)

[AndreyB]

My old 0.1 board:

my_0.1.jpg

My new 0.4 board is mostly ready:

my_0.4.jpg

Damn it good grounds! If a spark is sparking, how comes you need BETTER ground to actually start the car?! Note the cool 3D plug covers by @ and vertical coil drivers in the proto area. Now need smaller high side power switch board.

[AndreyB]

[video][/video]

[AndreyB]

this signal is supposed to be 50% duty cycle with all tooth the same width, but that's the tragedy of VR type of sensor: only the rises are reliable, the falls are pretty much useless for precise angle measurement.

[abecedarian]

this signal is supposed to be 50% duty cycle with all tooth the same width, but that's the tragedy of VR type of sensor: only the rises are reliable, the falls are pretty much useless for precise angle measurement.

That's going to depend mostly on the correlation between tooth face and VR sensor. If the sensor is isn't matched to the trigger wheel, the voltage will rise as the tooth enters, then fall to zero, then drop below zero as the tooth leaves the sensor, or vice versa if wired in reverse... which might be something worth checking if you're triggering isn't working as expected.

Code: Select all

tooth: \   /      versus: \       /   or: \   /
        \_/                \_____/         \_/
         _                    _            ___
sensor: | |                  | |          |   |

... for instance ... the first would be correct, the 2nd and 3rd are mismatched and will give erroneous voltages leaving you stuck trying to catch either the zero going positive edge or negative going zero edge.

MAX9924/6 set up as mode A2, I believe, is supposed to catch the positive-going-negative zero crossing, so VR polarity is important, as is matching the sensor to the trigger as mentioned. If the trigger's top (face) and bottom (valley between teeth) lands are different widths you won't get 50% duty no matter what you try. Also, if they're different and the VR polarity is reversed, the chip will be trying to detect a tooth when the sensor is actually looking at the space between teeth, because it's looking for the positive-going-negative zero crossing, creating a situation much like what I ASCII-art drew above.

Also, the MAX chips use the positive edge to set hysteresis levels making polarity even more important to proper function.

[kb1gtt]

From this page, http://www.diycardoctor.com/cam_sensor.htm see below signal. Note the typical OEM wave form has one edge that is clearly a valid edge, but the other edge kind of hangs around 0V. As well that will really hang around 0V when you have a skipped tooth. Most detectors are a 0V crossing detector with a hysteresis window to prevent nuisance trips. That nuisance tripping is a fair part of what makes the 9926 special. It automatically scales they 0V crossing sensitivity based on the peak detected. In the below picture you can see the raising edge 0V crossing's are very much blah, and the actual crossings could vary by large tolerances. While the falling edge is very clear when it crosses. In your case you appear to have the wires flipped which flips the signal, and flips which edge is accurately detected.

[AndreyB]

IMAG1721.jpg

More VR fun.
The green board is the older one - it has rusty water spots and it used to be a Honda board and you can see it's a mess of wires. Problem is this boars gives me a nice signal on both channels:

screenshot_ok.png

While the brand new super clean red board to which I want to upgrade shows me some crap on the second channel:

screenshot_broken.png

And so far I am failing to find the issue - all the connectivities are where they should be. Will re-heat the whole thing, hopefully it's just a bad solder joint somewhere, Hate to be stuck on such trivial things

[kb1gtt]

This was VR? I thinks your VR wires are flipped. The falling edge vs rising edge thing.

[AndreyB]

And so far I am failing to find the issue - all the connectivities are where they should be.

cursing on the forum has worked! I've located the bad solder joint - it was that jumper spot on the output side. Since output side is so much simpler I was not even looking there. Lesson learned: poor joint would somewhat work even on a digital line.

[AndreyB]

Got back from Michigan, temperature here dropped to about 30F/0C. Cold dodge would not start on 75% diesel/25% gas - sometimes it catches but then it dies, spark plugs are wet.

Bigger issue: discovery which was inserted into Frankenso 0.4 inside a case under the hood in a warm garage has died (this one now has "1" drawn on it): a bunch of system LEDs blink randomly as if there is a power issue. Took another discovery which was in the garage as well and somehow 10 minutes later this one would not recognize ST-LINK as USB device while rusEfi seemed to be running fine (this one has "2" drawn on it). Had to grab another one from upstairs to use OEM fuel pump to remove the diesel mixture.

Now the Neon is back on the road on pure gas but today two discovery boards have left for a better place This makes me upset since I have no clue why.

[kb1gtt]

My condolences and sorry for you loss

Hmm, I wonder why that could happen. You only replaced the discovery board, correct? So the 5V seems to be generating 5V? Does he discovery match any of the situations noted here http://rusefi.com/wiki/index.php?title=Hardware:stm32f4discovery_repair

[AndreyB]

Looks like Neon uses Bosch 0280155976 injectors, I will start by using http://www.boschdealer.com/specsheets/0280158117cs.jpg since that's better then nothing. Unless somebody can point me at a more relevant calibration summary?

[AndreyB]

I like how the end result of this looks like but I really want move on for now, hopefully my 0.333 alpha would server me good enough.

Today auto-tune session: https://svn.code.sf.net/p/rusefi/code/trunk/misc/logs/2003_dodge_neon/2016-01-30_autotune.zip

[AndreyB]

Now that I am done with that warm-up PID and resolved the no-start-due-to-no-gas issue, I need to get back to acceleration enrichment. Short test drive today just for a record:

https://svn.code.sf.net/p/rusefi/code/trunk/misc/logs/2003_dodge_neon/DataLogs/2016-02-15_21.09.49_drive2.msl

[kb1gtt]

I see CLT jumps from 88C to 103C. That's quite a swing, your thermostat might be a bit bad. Is that hard to change? I'd bet you get better CLT regulation if you change your thermostat.

Thermostats have a “rated” temperature such as 180F (82.2C) or 195F (90.6C)
This is the temperature the thermostat will start to open, give or take 3 degreesF (1.7C)
The thermostat fully open about 15(8.3C)-20(11.1C) degrees above its rated temperature

Found here http://www.stant.com/index.php/english/products/consumer-products/thermostats/abcs-thermostats/

Your thermostat appears to be going full open, which I do not expect at light engine loads with cold temperatures. This change in CLT is likely one source of control jitter that's causing some problems for tuning.


I see the AFR still spikes at times, but seems much better than it was. The AFR spikes on accell appear to be less than 1 second, which seems most common at low TPS changes, like an 8% TPS change seems to bring the most AFR spike. If you tromp on the long pedal a bit more TPS of 25%, it seems your AFR is better. So you seem to be tuning in the correct direction. I think you are currently hitting limits with your tuning because of system jitter.

I thought I remembered you showing me a injector compensation for voltage. I'm not seeing a change in the fuel:pulse based on voltage. Perhaps that's because the compensation would have a minimal change, perhaps something else is happening. I can't find the table right now, so I can't tell you if that compensation is happening or not.

[AndreyB]

With life in the way it has been about a month since I've started my test mule on rusEfi. Good news current firmware is still functional, not so good news is poor start with weak battery: note how trigger synchronization is lost after one cycle of ignition/injection.

Once the battery spent 3 minutes on 50A charge the car has started right away-ish.

Defect ticket: https://sourceforge.net/p/rusefi/tickets/279/

[AndreyB]

Summer is great time to test A/C logic. Looks like ECU reads the switch state and turns the relay accordingly? Probably no A/C while cranking and no A/C while wide open throttle? Also radiator fan always on in A/C is on?

http://rusefi.com/wiki/index.php?title=Vehicle:Dodge_Neon_2003#A.2FC

[kb1gtt]

Also use a pull up resistor on the AC sense switch, and if you sense 0 volts, turn off AC, if you see +V then it's OK to use the AC. That's a safety that prevents over pressurizing which results in bursting, as well it prevents operating when your compressor is in suction which prevents the oil from getting around the system and can damage your compressor.

[AndreyB]

Test mule is having a tantrum - no cam sensor signal. I guess there should be no oil there, but cleaning did not help. Ordered new sensor, tomorrow I will try to run with only crank sensor.

At lest that happened while inside the garage.

[AndreyB]

That thing behind the sensor must be my camshaft right? It is kind of supposed to spin right?

[video][/video]

[AndreyB]

Timing belt is not moving while crank pulley is moving. That's an interference engine, so looks like RIP grey Neon.

[stefanst]

[AndreyB]

Actually looks like that's fixable - the valves look good and there are no marks on the pistons. Kudos @ for convincing me to check before destroying the harness!

[video][/video]

[AndreyB]

Funny thing - it was one of the #4 cylinder valves which was kind of leaking above average but we have found some marks after cleaning the pistons on cylinder #3. #3 valves were not leaking!

The car runs with new belt/HG & listed for sale on local CL.

[stefanst]

Congrats on getting it back up and running again.
Just out of curiosity: how much did you list it for?

[AndreyB]

I hate this negative electricity. Positive stuff is OK, but the negative... There is no place for it. http://forum.2gn.org/viewtopic.php?p=1016987#1016987

[stefanst]

Damn. If you have negative electricity going on, there's probably some positrons flowing in all the wrong directions.

So we believe the GND from battery to headlight is solid and yet the wipers start going when you turn on the headlights?
Then it can't really be a ground fault. If the headlights turned on, when you turn on the wipers, then it could be faulty ground on the wipers. But the other way round does not indicate a ground problem to me.

[AndreyB]

I am a blind idiot - there was a disconnected ground next to the passenger headlight. Once I've connected that group the wipers are no longer activated by the headlight. Now back on the road to get p0551 resolved hopefully second inspection attempt would be a winner. The nice NJ DMV people have failed my EMISSION INSPECTION for POWER-STEERING MALFUNCTION because... BECAUSE IT's a check ENGINE light

[stefanst]

Power Steering fault could be caused by lack of signal from PS pressure witch. Short the switch and see what happens?

[kb1gtt]

My brother who at the time was in NH, once had to junk a car because the tach failed. When the tach failed it causes a check engine code, which did not trigger the dash light, but did trigger the state inspection tool. The issue was that the tach was clobbering part of a data packet on the transmission bus. Replacing the transmission controller and / or dash display were the only options, and these options had high probability of needing a re-program from a dealer. The car had no rust, and functioned perfectly. However he couldn't get a sticker on it, so he ended up having to junk it. Basically any options to fix it cost more than the car was worth, and it was lower cost for him to get a different car.

Good luck. Did you top off your windshield fluid? If not I bet they fail you for that

[AndreyB]

Inspected and sold. End of an era