Won't Reset for Smog Test; P0125/ 0173/ 0300/ + Cruise Control/ Speed Sensor Error

cr4x4cruiser

Observer
1998 Montero SR
110.000 original miles
New Timing Belt/ Water Pump/ Gaskets/ Seals/ Plugs/ Wires/ Blah, blah, blah...


Have attempted several times over the past few weeks [other parts of life interrupt] to get the ECM to reset, or ready itself for a smog test [CA].

Literally, have driven it on three 150-mile round trips, in the middle of the night [only way to cruise @ 60mph in/ around Los Angeles].

>> While out on test runs the rig is plugged into an INNOVA 3160d Scan Tool <<

First trip resulted in an error code [P0172] for Bank 1 / System Too Rich, which led us to replace the original - upstream - O2 Sensor.

But, it did not allow us to reset everything, or get us to the smog test.



Latest trip resulted in the following;

1] After getting on freeway, I could not engage the Cruise Control... issue never happened prior - but really only used on two previous trips.

2] A code appeared shortly after, declaring a problem with the CC or Speed Sensor [sorry, trying to drive @ 60mph and reading tiny print is impossible for me]. As well, I am an idiot for deleting the code prior to memorizing it.

3] After driving south 75 miles, to Oceanside ["that's too far..." - yeah, it may be], another code popped up; P0173 / Fuel Trim [Bank 2]... as well, the "Check Engine" finally triggered.

4] Turned around, and ended up driving north about 20 miles before pulling into a gas station to reset the scanner...

5] No sooner did I pull in than P0300 [Random Misfire] appeared...

6] Erased the codes... Check Engine light went off.

7] Headed back up the road, and P0125 [Insufficient Coolant Temp for Closed Loop System] declared itself...

8] Got home, stewed for awhile, went to bed [3:30am].


Plenty of possibilities here... BUT, would anyone care to agree with the following;

After going over it most of the day, considering what parts to throw at it, the "light bulb" moment occurred...

While discussing it with a friend, it dawned on me that when I initially connected the scanner to the truck the voltage was reading at about 11.50 volts... later, it was showing 10.50 volts.

As well, the dash gauge certainly did not appear to reach the same voltage level indicated as our '99 SR [not scientific, but it struck me as odd].


I suspect a malfunctioning Alternator...

- which could definitely affect the voltage being applied/ required for a plethora of sensors on the truck, right?

- like the Mass Airflow Sensor.

- or, Cruise Control.

- or, input required for an O2 Sensor.

- maybe even a sensor for the Coolant Temp.


We're taking it in tomorrow for diagnostics I am unable to perform... but I would appreciate your input/ opinion on such.


Is it very possible a malfunctioning Alternator could cause a bunch of FALSE error codes?

Tell me I'm on the right path... tell me I'm wrong... lecture me... school me.

Thanks to all,

Wm.



p.s. [we felt like I showed up with a "trailer queen" @ MOD 2017... especially when the "AZ Crew" pulled in... those boys ain't playing! well, yeah they are... not afraid of putting scars on their rigs]
 

ryandavenport

Adventurer
Typically if you get a misfire code, you will have a misfire. The rich codes are most likely related to a misfire caused by overfuel, either an injector sticking open, or ignition occurring at the wrong moment. Most people go by feel as the judge of whether you have a misfire, but it could be so faint that you don't feel it. I would diagnose that first before looking too far into the other stuff.


Sent from my iPhone using Tapatalk
 

EyeInTheSky

Adventurer
Easy check is to see how much voltage your alternator is putting out, as well as checking for AC voltage. Also, how's your battery?
 

KyleT

Explorer
Are these hard faults or pending codes? What is the status of the emission monitors?


Sent from my iPhone using Tapatalk
 

NatersXJ6

Explorer
I've never owned a montero but have had both alternator and battery cell failures cause seemingly random and unrelated trouble codes to register in other obdII vehicles as voltage drops. Easy to diagnose, so test it, replace if necessary, and keep troubleshooting.

Good luck.
 

jeep-N-montero

Expedition Leader
I had never put much thought into it before, but I used to get an intermittent CEL for the TPS voltage but has not occurred since the new alternator about a year ago.
 

cr4x4cruiser

Observer
P0300/ Misfire: If there is one, it is negligible...


Voltage Output: This is my whole point... I suspect that many of these issues can be directly caused by/ related to voltage/ amp drops/ spikes caused by a faulty electrical system. Before chasing rabbits down other holes [fault codes] we should test the electrical system to ensure no possibility of failure/ unwanted gremlins affecting the ECM.


Active Code [Hard Fault / Live Code]:
P0173 /

Pending Codes:
P0125, P0300


Emission Monitors:
Evap is "not ready" [acceptable in CA]
Catalytic is "not ready" [unacceptable in CA]
All others appear complete/ ready [per Smog Test Technician]


=========================


Everybody has their opinion, especially when it comes to cycling your vehicle for emissions testings;

OBD Auto Doctor / OBD drive cycle

"The purpose of the OBD2 drive cycle is to let your car run on-board diagnostics. This, in turn, allows the readiness monitors to operate. And detect potential malfunctions of your car's emission system. The correct drive cycle for your car can vary greatly depending on the car model and manufacturer. Also, the monitor in question affects the required drive cycle.

Today, many vehicle manufacturers include these drive cycles in the vehicle owner's manual. Typically, a few days of normal driving, both city and highway, will make the monitors ready. The following generic drive cycle can be used as a guideline if a specific drive cycle is not known. It will assist with resetting monitors when a car specific drive cycle is not available. However, it may not work for all cars and monitors.

The drive cycle can be difficult to follow exactly under normal driving conditions. Thus, it is better to drive it in restricted area!

The universal OBD-II drive cycle begins with a cold start. You should have coolant temperature below 50 C/122 F, and the coolant and air temperatures within 11 degrees of one another. This condition can be achieved by letting the car to sit overnight.

The ignition key must not be left ON position before the cold start. Otherwise the heated oxygen sensor diagnostic may not run.

Start the engine and idle the engine in drive for two and half minutes, with the A/C and rear defroster on if equipped.

Turn the A/C and rear defroster off, and speed up to 90 km/h (55 mph) under moderate, constant acceleration. Hold at a steady speed for three minutes.


Slow down to 30 km/h (20 mph) without braking. Do not depress the clutch if you are running with manual transmission.

Speed up back to 90-100 km/h (55-60 mph) at 3/4 throttle. Hold at a steady speed for five minutes.

Slow down to a stop without braking."


==========================

Neglected maintenance preceded the timing belt change...
Battery disconnect preceded this smog test preparation...
I am wagering an electrical gremlin is at fault...
Thanks for the input...
 
Last edited:

cr4x4cruiser

Observer
Additional Notation:

Alternator is original - as far as I can tell...

The battery is new [months old], Costco-branded Interstate, of the correct physical size/ group/ CCA specified for this Montero...

All cables/ connections appear clean & intact...

Proper voltage for a battery should be 12.7 volts...

Proper Charging for an Alternator should read between 13.7 & 14.7 volts...

The scan tool noted readings of between 11.5 & 10.5 volts - while the vehicle was on & under load [being driven].

The I/M [Inspection/ Maintenance] Readiness Monitors, at the top of the Scan Tool, would be flashing while we are driving.
Then they eventually start going solid - indicating they are ready, or the cycle is complete.
However, it would not be long [under 20 miles/ just a few miles] before the same monitors would start flashing, again.
At first, I suspected a loose connection with the DLC [Data Link Connector] port... that is not the case.
This, to me, is another indication of vehicle electrics not being in perfect working order, and likely resulting in errant voltage drops/ spikes.
Hence, the I/M Readiness Monitors alternating between ready & not ready.

I will be putting the rig in the shop today [Friday]... by Monday afternoon I suspect we shall learn of the results.
 

jeep-N-montero

Expedition Leader
Install a new alternator and report back, if the charging system isn't sending the proper voltage to the sensors then the sensors cannot do their job properly, makes sense right? BTW, the quickest way to kill a new battery is a bad alternator, and most battery retailers now require proof of a properly functioning alternator before they will warranty out a "bad" battery.
 

TheMole

Adventurer
Emission Monitors:
Evap is "not ready" [acceptable in CA]
Catalytic is "not ready" [unacceptable in CA]
All others appear complete/ ready [per Smog Test Technician]


Actually, I had my cat "not ready" and passed just fine about a year ago. According to the CA smog reference guide below, you can have a max of 1 incomplete monitor for 96-99 vehicles so you just need to get one more of your monitors ready.

https://www.bar.ca.gov/pdf/Smog_Check_OBD_Reference_Lite_Version.pdf


My post from last year and more info from OP:

http://forum.expeditionportal.com/t...o-Need-To-SMOG-Their-Car/page4?highlight=smog
 

kalieracer

Observer
If you are in LA, and need some to look at the truck call Chai at C&A 8189019757. Both and his partner are master Mitsubishi techs. Their shop basically works on only old Mitsubishi's and DSMs
 

cr4x4cruiser

Observer
Mole,

I saw your prior posting...

Truck is still @ shop, awaiting its turn in line [told owner it could be put aside if busy]...

Aware of having 1 monitor on is acceptable...

Know that 2 monitors is a fail...

We want it to run as it was meant to...

We don't want to "trick" the system...

We'll find out something, sooner than later...

My money is still on an electrical/ voltage issue...

Thanks for the input,

Wm.
 

jeep-N-montero

Expedition Leader
Mole,

I saw your prior posting...

Truck is still @ shop, awaiting its turn in line [told owner it could be put aside if busy]...

Aware of having 1 monitor on is acceptable...

Know that 2 monitors is a fail...

We want it to run as it was meant to...

We don't want to "trick" the system...

We'll find out something, sooner than later...

My money is still on an electrical/ voltage issue...

Thanks for the input,

Wm.

So why didn't you fix the voltage issue before taking it in?
 

cr4x4cruiser

Observer
"Install a new alternator and report back, if the charging system isn't sending the proper voltage to the sensors then the sensors cannot do their job properly, makes sense right? BTW, the quickest way to kill a new battery is a bad alternator, and most battery retailers now require proof of a properly functioning alternator before they will warranty out a "bad" battery."

Plus;

So why didn't you fix the voltage issue before taking it in?


A] We are not simply going to throw new/ rebuilt parts at it... we'll find out exactly what the issue may/ may not be.

B] Not having a proper garage/ shelter and living in L.A., the sun actually does a number on ya'... I'm beyond the age and mindset that I can do anything, especially when I can have my mechanic do it properly - and for minimal outlay.

Then again, having continued to cull as much information as possible, it would appear that this generation of Monteros [2.5] has this issue [Smog Test Readiness] crop up ad nauseam...

I suspect this coming week will bring about the diagnosis & appropriate repair required.
 

cr4x4cruiser

Observer
UPDATE, 6SEP17:

Overall Test Results

Comprehensive Visual Inspection: PASS
Functional Check: FAIL
Emissions Test: PASS

Because the two monitors refuse to reset the result is a fail.


Things we have done;

1] Alternator replacement

2] Fuel Filter replacement

3] Fuel Cap replacement

4] Octane boost; 91 octane + 100 octane [Pasadena 76 station] > 93+ octane

We can drive until the cows come home, I doubt these [EVAP / Catalytic Converter monitors] will ever reset...


ASM Emission Test Results

15 mph / 1648 rpm: CO2 [%] MEAS: 14.40 O2 [%] MEAS: 00.11 HC [ppm] MEAS: 33 AVG: 7 MAX: 46 CO [%] MEAS: 00.12 AVG: 00.03 MAX: 00.58 NO [ppm] MEAS: 21 AVG: 90 MAX: 488
25 mph / 1662 rpm: CO2 [%] MEAS: 14.40 O2 [%] MEAS: 00.06 HC [ppm] MEAS: 23 AVG: 6 MAX: 29 CO [%] MEAS: 00.14 AVG: 00.03 MAX: 00.72 NO [ppm] MEAS: 16 AVG: 84 MAX: 741

Finally, a P0421 Code [Warm Up Catalyst Efficiency Below Threshold] came up...

High HC [Hydro Carbons] is likely the result of a Catalytic Converter failing [my opinion, all else being in working order]...

High CO [Carbon Monoxide] is likely the result of a Charcoal Canister that is failing [my opinion, all else being in working order]...

Low NO [Nitrogine Oxide] is likely the result of the vehicle not being hot enough during the smog test... then again, that does not look right at all. A failing Catalytic Converter should showed extremely high readings for NO... tests error, maybe...


Ultimately, this failed because of the monitors not resetting... we are sourcing a new - C.A.R.B. approved - Right Front Catalytic Converter, as well as a charcoal canister...

We'll keep ya' posted... it's so fun to do things the legal way in L.A.

- Wm.
 

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