98 GT Needs Starter Fluid to start

Steve50013

New Member
Jan 14, 2020
6
0
1
29
Texas
1998 GT will start when using starter fluid and will remain running with a strong idle.

I purchased the car not running and replaced the fuel pump and fuel filter. I was then able to start the car a few times but not consistently. The idle was weak so I proceeded to change out the Idel Air controller, Mass Airflow Sensor, and the Crankshaft Position Sensor. I also installed a cold air intake since the intake housing was damaged by the previous owner.

Everything that I have replaced: spark plugs, sparkplug wires, battery, alternator, Mass Airflow Sensor, Crankshaft Position Sensor, Idle Air Controller, Water pump, serpentine belt, and thermostat.

I have a secondary issue in which I most likely have a vacuum leak that I am still looking for. Since after installing the CAI and the IAC it dies when revved. When I get home I'm going to put the old air intake housing back in to see if the issue stays.

Edit: Forgot to mention there are no codes.
 
Last edited:
  • Sponsors(?)


wmburns

SN Certified Technician
Aug 14, 2009
5,676
471
164
Houston Texas
Are you looking for advice? Stop replacing parts trying to resolve a problem. Test more and replace parts that are known bad.

Do you have an ODB2 scanner? If you did it might make short work of this car's trouble shooting. Likely the ODB2 scanner could have been purchased already using the $'s already spent on parts.

ForScan ODB2 scanner w ELM327 USB

Note for example.
  • It's unlikely that a CKP sensor could be so bad that the motor can't start but it can run.
  • It's unlikely that bad EGR valve could cause a no start BUT it runs OK once started.
However, a large vacuum leak could cause a no start.

What are some other "possible" causes for your issue? Example:
  • Incorrect fuel pressure
  • excessive fuel pressure leak down
  • non functioning high speed/low speed fuel pump relay.
  • clogged fuel injectors
  • clogged fuel filter.
  • stale or bad gas.
  • Low system voltage (not enough voltage to operate the ignition).
  • vacuum leak between the MAF and throttle body.
  • MAF sensor sending incorrect value to PCM.
  • Weak ignition.
  • incorrect temperature inputs to PCM (IAT or ECT). An incorrect temperature can cause the PCM to not apply the correct fuel enrichment for the given conditions.
  • incorrect IAC valve (non black vented version used in a vented application).
  • base motor problem such as low compression.
  • perhaps tons of other "possible" causes.
Generally speaking. IF you think there's a bad part in need of replacing, there's a test that can help rule it in or out before replacing it.

1996+ Crank with no start check list
 

Steve50013

New Member
Jan 14, 2020
6
0
1
29
Texas
I have a scanner and no codes come up.

The car was sitting for about 4 years before I purchased it. So most of the parts I have replaced needed replacing:
Fuel Pump = BAD
Fuel Filter = Unknown last change so replaced
Spark Plugs = Unknown last change so replaced
Serpentine Belt = Unknown last change so replaced
Spark Plug Wires = Unknown last change so replaced
Water pump = Leaking so replaced
Thermostat = Replaced due to replacing water pump
Battery = Went bad so replaced
Alternator = Wasn't charging the battery so replaced
IAC = Car idled poorly so replaced

The only parts that probably were not necessary to replace were the MAS and the CKP. The car does idle better after having these replaced though.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,676
471
164
Houston Texas
I have a scanner and no codes come up.
I'm asking for more information than just "no DTC" codes come up. Accessing just DTC codes is a reader. Where as an advanced scanner can monitor operational PID's.

For example do you know what the PCM "thinks" the value of:
  • The engine coolant temperature (ECT)
  • The input air temperature (IAT)
  • The MAF flow during cranking and running?
  • The RPM's during cranking?
  • The IAC duty percentage?
Don't discount that your problem could be as simple as a bad or open IAT sensor signal. Why? Because an open IAT will cause the PCM to "think" that the outside air temperature is -40 degrees and adjust the fuel enrichment to match. This is where an ODB2 scanner can answer this question in mere seconds.

To trouble shoot the EGR system, monitor the EGR flow via the DPFE sensor. If zero DPFE flow, then it's unlikely EGR is causing a problem.

It will be necessary to measure the fuel pressure with an external gauge.

What did you do about the possibility of stale gas? 4 years is very old for gas. One of the symptoms of stale gas is poor vapor pressure. IE it's hard to ignite.

Note, when setting for extended periods of times, sometimes the fuel injectors will gum up. If this is suspected, consider an injector cleaning and flow test service such as InjectorRX.com. I have revived several cars that sat for an extended period of time. When doing major motor work I routinely send the injectors out for cleaning. Allows to start the project with a set of known goods.
 

Steve50013

New Member
Jan 14, 2020
6
0
1
29
Texas
I'm asking for more information than just "no DTC" codes come up. Accessing just DTC codes is a reader. Where as an advanced scanner can monitor operational PID's.

What did you do about the possibility of stale gas? 4 years is very old for gas. One of the symptoms of stale gas is poor vapor pressure. IE it's hard to ignite.

Note, when setting for extended periods of times, sometimes the fuel injectors will gum up. If this is suspected, consider an injector cleaning and flow test service such as InjectorRX.com. I have revived several cars that sat for an extended period of time. When doing major motor work I routinely send the injectors out for cleaning. Allows to start the project with a set of known goods.
I'm sorry I had misunderstood at first. I'll see if my scanner has access to that information (I think it does).

As far as gas it was bone dry when I purchase it. I put a gallon or two of fresh gas in after replacing the fuel pump.

I'll update once I check some of the PID numbers.
 

Steve50013

New Member
Jan 14, 2020
6
0
1
29
Texas
I'm asking for more information than just "no DTC" codes come up. Accessing just DTC codes is a reader. Where as an advanced scanner can monitor operational PID's.

For example do you know what the PCM "thinks" the value of:
  • The engine coolant temperature (ECT)
  • The input air temperature (IAT)
  • The MAF flow during cranking and running?
  • The RPM's during cranking?
  • The IAC duty percentage?
Don't discount that your problem could be as simple as a bad or open IAT sensor signal. Why? Because an open IAT will cause the PCM to "think" that the outside air temperature is -40 degrees and adjust the fuel enrichment to match. This is where an ODB2 scanner can answer this question in mere seconds.

To trouble shoot the EGR system, monitor the EGR flow via the DPFE sensor. If zero DPFE flow, then it's unlikely EGR is causing a problem.

It will be necessary to measure the fuel pressure with an external gauge.

What did you do about the possibility of stale gas? 4 years is very old for gas. One of the symptoms of stale gas is poor vapor pressure. IE it's hard to ignite.

Note, when setting for extended periods of times, sometimes the fuel injectors will gum up. If this is suspected, consider an injector cleaning and flow test service such as InjectorRX.com. I have revived several cars that sat for an extended period of time. When doing major motor work I routinely send the injectors out for cleaning. Allows to start the project with a set of known goods.
So I finally got some testing done. I got 3 sets of data from my scanner once right after start, once after about 10min, and one from after the engine is at running temp.

A code did end up coming up after about 35-40min of idling for P0172 System too Rich Bank 1.

I went ahead and downloaded the data from my scanner, since it takes "snapshots" of live data it ended up being 86 pages of data.

I'll attached it to this reply. To save time from digging through data here are some snipets:


Right after start: (page 1)
Live Data Numbers of DTCs 0 Fuel system 1 statusOL Fuel System 2 status-Calculated Load Value(%)21.6 Engine Coolant Temperature(øC)39 Short Term Fuel Trim -Bank 1(%)2.3 Long Term Fuel Trim - Bank 1(%)0.0 Short Term Fuel Trim -Bank 2(%)2.3 Long Term Fuel Trim - Bank 2(%)0.0 Engine RPM(rpm) 920 Vehicle Speed Sensor(km/h)0 Ignition Timing Advanece for #1 Cylinder(ø)25.5 Intake Air Temperature(øC)16 Air Flow Rate from Mass Air Flow Sensor(g/s)8.54 Absolute Throttle Position(%)20.8 Location of Oxygen SensorsB1S12--B2S12-Oxygen Sensor Output Voltage Bank 1-Sensor 1(V)0.860 Short Term Fuel Trim Bank 1-Sensor 1(%)2.3 Oxygen Sensor Output Voltage Bank 1-Sensor 2(V)0.000 Short Term Fuel Trim Bank 1-Sensor 2(%)N/A Oxygen Sensor Output Voltage Bank 2-Sensor 1(V)0.855 Short Term Fuel Trim Bank 2-Sensor 1(%)3.1 Oxygen Sensor Output Voltage Bank 2-Sensor 2(V)0.000 Short Term Fuel Trim Bank 2-Sensor 2(%)99.2 OBD requirements to which vehicle is designedOBDII

After about 10min:
Numbers of DTCs 0 Fuel system 1 statusCL Fuel System 2 status-Calculated Load Value(%)21.2 Engine Coolant Temperature(øC)46 Short Term Fuel Trim -Bank 1(%)-18.8 Long Term Fuel Trim - Bank 1(%)0.0 Short Term Fuel Trim -Bank 2(%)-20.3 Long Term Fuel Trim - Bank 2(%)0.0 Engine RPM(rpm) 921 Vehicle Speed Sensor(km/h)0 Ignition Timing Advanece for #1 Cylinder(ø)29.5 Intake Air Temperature(øC)16 Air Flow Rate from Mass Air Flow Sensor(g/s)8.27 Absolute Throttle Position(%)20.8 Location of Oxygen SensorsB1S12--B2S12-Oxygen Sensor Output Voltage Bank 1-Sensor 1(V)0.640 Short Term Fuel Trim Bank 1-Sensor 1(%)-19.5 Oxygen Sensor Output Voltage Bank 1-Sensor 2(V)0.000 Short Term Fuel Trim Bank 1-Sensor 2(%)N/A Oxygen Sensor Output Voltage Bank 2-Sensor 1(V)0.855 Short Term Fuel Trim Bank 2-Sensor 1(%)-20.3 Oxygen Sensor Output Voltage Bank 2-Sensor 2(V)0.000 Short Term Fuel Trim Bank 2-Sensor 2(%)99.2 OBD requirements to which vehicle is designedOBDII

Then after the engine got hot: (Page 78-79)
Numbers of DTCs 0 Fuel system 1 statusCL Fuel system 1 statusCL Fuel System 2 status-Calculated Load Value(%)28.6 Engine Coolant Temperature(øC)95 Short Term Fuel Trim -Bank 1(%)-11.7 Long Term Fuel Trim - Bank 1(%)-25.0 -10.2 -10.2 -25.0 -25.0 Engine RPM(rpm) 657 Vehicle Speed Sensor(km/h)0 Ignition Timing Advanece for #1 Cylinder(ø)16.5 Intake Air Temperature(øC)23 Air Flow Rate from Mass Air Flow Sensor(g/s)5.82 Absolute Throttle Position(%)20.8 Location of Oxygen SensorsB1S12--B2S12-nk 1-Sensor 1(V)0.305 nk 1-Sensor 1(V)0.305 sor 1(%)-10.2 sor 1(%)-10.2 nk 1-Sensor 2(V)0.810 Short Term Fuel Trim Bank 1-Sensor 2(%)N/A Oxygen Sensor Output Voltage Bank 2-Sensor 1(V)0.800 Short Term Fuel Trim Bank 2-Sensor 1(%)-13.3 Oxygen Sensor Output Voltage Bank 2-Sensor 2(V)0.715 Short Term Fuel Trim Bank 2-Sensor 2(%)99.2 le is designedOBDII le is designedOBDII


My scanner also had some built in testers for fords here are the ones that came up as fail: (Pages 83-end)
Cylinder Events Tested ID() 00 TEST() 85A9 MAX() FA0 STS() Fail

Total Engine Misfire Rate & Type B Threshold ID() MOD() $10 MIN() ---STS() Fail

Not10 front Switch Ratio Bank 2 ID() 21 TEST() 3F MAX() 19 STS() Fail
 

Attachments

Steve50013

New Member
Jan 14, 2020
6
0
1
29
Texas
Also, I put the old IAC back on and the car kept on dying at idle.

So I put the new one back on and it stayed on during idle although the idle did run a bit rougher than before.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,676
471
164
Houston Texas
From what I can see looking at the data the PCM does not have good fuel control. The O2 sensors are rarely switching lean. This is causing the PCM to add more and more fuel in an attempt to get the O2 sensors to start switching rich/lean.

Please listen to the next part of what I'm trying to tell you. More tests are needed to try and determine WHY the O2 sensors are not switching. This is not a call to replace something. Some possible reasons I can think of off the top of my head are:
  • chronic misfire, Note, the lack of fuel control can cause misfire (IE are the misfires the problem or a symptom).
  • High fuel pressure
  • fuel pump high/low speed relay stuck in high position. (1998 model year only).
  • Fuel pump too large for the motor's requirements. IE moving more fuel than the regulator can return.
  • incorrect fuel injectors. IE the size of the fuel injectors do NOT match the PCM tune.
  • stuck open fuel injectors
  • Incorrect MAF sensor output
  • bad front O2 sensors
  • bad PCM.
Since you bought the car in distress, let's cover some of the "mods" that the prior owner might have made in an attempt to "go fast". Are you POSITIVE that the fuel injectors are correct for this application?

Does the exhaust actually smell RICH? Why is this important? Because this confirms IF the motor is actually running rich.

Have you MEASURED the fuel pressure?

Are you POSITIVE that the fuel regulator return line is not blocked?

Does the fuel pressure actually respond to changes in intake manifold vacuum? IE if the intake vacuum reference line is disconnected and plugged, does the fuel pressure jump to 40 PSI? Is there vacuum present at the intake manifold reference line?

If this were my car the first thing is to confirm that factory sized fuel injectors have been used.

Next is to actually measure the fuel pressure. Almost all auto parts stores will rent tools. So there's no excuse not to use the correct tool for the job.

Then I would do some quick tests to confirm that the O2 sensors are actually responding to changes. I would monitor the front O2 sensor voltage while the motor is running. Then pull the fuel pump fuse. What we want to see is IF the O2 sensors start to switch as the motor begins to run out of fuel. It may be easier to see the change by monitoring short term fuel trims (STFT).

Another way to perform this test is to create a vacuum leak down stream of the MAF sensor while monitoring STFT's. What you are looking to see is IF STFT's go up in response to the created vacuum leak.

I did quite a bit of work reformatting your data into a format where I could see HOW each PID changes over time. IMO this is beyond the call of duty. So if you just post the raw data and expect someone to analyze it for you, I'm out. You will need to carry a greater share of your own weight from here on.

My Ford service manual list the "reasonable" hot idle MAF values as 0.6-0.9 volts. I don't have an easy way to convert g/s into voltage. Many scan tools are capable of displaying PID's in different units of measure. Not a bad idea to monitor the MAF voltage PID to see that if falls in a "reasonable" range. If it's higher than it should be, this could cause the PCM to dump more fuel than the motor needs.
 
Last edited:

wmburns

SN Certified Technician
Aug 14, 2009
5,676
471
164
Houston Texas
I put a new intake manifold on my 2000 GT today. While checking my work I took note of the MAF flow at a hot idle was 0.66 - 0.70 lb/minute. Google says that .66 lb/min is equal 4.98952 g/s. This might suggest that your MAF value is slightly high.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,676
471
164
Houston Texas
Looking again at your data dump. Note how LTFT's and STFT's act. Both go negative (taking away fuel). I also think this is why the O2 sensors do not switch rich/lean.

What would cause this? How about IF the MAF is overstating the air flow?

What one symptom of a dirty MAF sensor? It OVER states at low flow and UNDER states at high flows. This creates a situation where the idle is rich but the motor is lean under load.

Doing some quick math it appears to me that the MAF sensor is overstating the air flow by at least 20% at idle. That's almost the exact amount of the STFT and LTFT.

Recommend getting yourself some CRC MAF cleaner (or any other brand made for this purpose) and throughly clean the MAF element. Be careful as it's easily damaged. Monitor the MAF air flow after cleaning to see IF the MAF air flow rates have changed (come down) from the values previously posted.

I suspect that once the LTFT's and STFT's get closer to zero this motor will run better.

The idle maybe a different issue. Best to tackle after the basic PCM closed loop fuel control is under better control.

In the mean time here's some information on HOW to trouble shoot an idle/IAC issue. Note for the 1996-1998 model year the IAC with the black vent is needed. IF the IAC vent is not opening as it should, this will create a hard start condition.

Troubleshoot IAC idle problems 1996-2004

Please do your fellow forums members a favor and update this thread with your experiences. This is a fairly difficult driveability issue for the home DIY'er to trouble shoot. This thread shows what can be done with an ODB2 scanner, data logging, and knowledge based analysis.

Good luck.
 
Last edited: