LT1 is alive! sort of...Need Help!

[gvincent]

Well the second LT1 is running kind of. I had to swap out a brand new Opti with my Opti off the first motor to get it started. There was no continuity on the brand new cap from the coil wire feed to the rotor button. I'm getting good at Opti swaps, done in 2 hours.

 

Now for the problem:

It runs like crap, #3 and #4 cylinders are not firing for some reason, this is what I have done so far:

1. put a spark tester on each spark plug wire, all test ok

2. Resistance check each injector, all test ok

3. apply 12 volts to each injector, some were stuck but all were clicking after tapping each solenoid with 12V they were all clicking.

4. bought a NOID light kit, all tested OK as receiving the negative pulses.

5. Fuel pressure is right at 45Lbs while running although bleeds right off. I found out I need to hook the Air bleed line in with the return, I will get this done after my AN adaptor and "T" fitting get here today.

6. Bought a compression gauge and removed all the spark plugs and did a compression check the results were:

Cylinder #1 200Lbs

Cylinder #2 195Lbs

Cylinder #3 200Lbs

Cylinder #4 190Lbs

Cylinder #5 200Lbs

Cylinder #6 193Lbs

Cylinder #7 190Lbs

Cylinder #8 204Lbs

Now after testing and putting the plugs back in I noticed that I forgot to wire the throttle wide open during the test. Each cylinder would increase it's pressure on each rotation.

7. While I had each brand new plug out I looked at them and all 6 plugs that had fired were black with a grey tip, the #3 and #4 cylinder looked like they had never fired, a little slight dis-colorization but that was it.

8. I went to hook up my Autoxray XP240, but half the LCD screen was not working so I couldn't read half of what it was reading in capture mode.

My Son had borrowed it and now it doesn't work, what else is new!

 

A few days earlier it read the following codes:

#43 Electronic Spark Control

#29 EAS Electrical Failure

#91 Shift Light Fault

#97 4K Pulse mile fault

The capture read:

Loop-Open

800 Idle

800 RPM

166.5 coolant

86.9 Manifold air

MAP 1.33V

Throttle 0.56

Throttle angle 0%

Mass 10gr/sec

CCP duty cyc 0.0

Battery 1.6V

BAR Pressure 4.90

Left O2 83

Right O2 193

Bl cell 16

Left block value 128

right block value 128

Integra value 128

Left Injector pulse 4.2ms

Right Injector pulse 4.2ms

Idle air meter 44 steps

Learned Idle 32 steps

Spark advance 22 degrees

Knock retard 0

Knock Sensor 245

EGR 0.0%

Fan 1 on

Fan 2 on

Air switch off

 

Last night I ran it longer to see if it would go into Closed loop and used the laptop with PCM Communicator.

Closed loop

Water temp 173

RPM 775

RPM Variation 1.66%

Air flow 9gm/sec

Desired Idle 800

Left O2 249mV

Right O2 688mV

Throttle position 0%

Left O2 BLM 128

Right O2 BLM 128

Left O2 Del 138

Right o2 Del 138

Battery 12.6V

TPS volts 0.57

IAC Pos 28

Baro 102kpa

In air temp 80F

Learn disabled

Spark 23 degrees

Knock retard 0.0

Knock count 9905

MAP 33kpa

Left pulse width 4.75ms

Right pulse width 4.82ms

BL Cell 16

Gerr -1

Input trans mode-performance

Input no TCC brake sw

Input no spark retard

Not power enriched

no kickdown pattern

no injector fault

both fans

3rd gear

A/C temp 40

A/C pressure 0.02V

 

Again I have a these 2 codes:

Code 29 EAS Electrical Fault (ODM)

Code 43 ESC failure

 

I can erase these 2 codes but the keep coming back,

My factory manual say that code 29 is an air pump code

and code 43 is a knock sensor code?

Both scanners say the same code number but a different description than the manual???

I did replace the Knock sensor, and I have exhaust leaks with the Sanderson headers, I need to install gaskets.

 

How much harm am I doing to the motor by running it on 6 cylinders?

What would cause cylinders 3 & 4 not to fire?

 

Sorry for the long post, but I wanted to get all the information down.

Thanks,

Greg

[mark]

Ill bet its the injectors. Swap a couple around and see if thoses cyclinders fire. It'll be OK to run on 6. I ran my lt-1 on 6 for a whole weekend at Roebling Road. No fun but no harm done.

[gvincent]

Ill bet its the injectors. Swap a couple around and see if thoses cyclinders fire. It'll be OK to run on 6. I ran my lt-1 on 6 for a whole weekend at Roebling Road. No fun but no harm done.

 

Yes it was the injectors, I took a chance and tested my other injectors on the other LT1 and found only 4 that would click with power applied and swapped 2 of them over to the engine, it runs on all 8 cylinders now!!!!!!

Amazing that the injectors just clog up like that from just sitting for a year, they were running just a year ago.

 

Now I still have the two codes to clear:

#43 Electronic Spark Control

#29 EAS Electrical Failure

 

I tested the new knock sensor and it is reading fine, right at 3300 ohms

I do not have the 5 Volts at the connector.

I am going to have to get the ECU back out from behind the dash and check for the 5 Volts at Pin D22 dark blue wire on the "D" blue connector, if present there I will have to run a new wire as there must be a break in it somewhere. If not present I am not sure what to do, possibly a bad PCM? or should I suspect the Knock module in the PCM? should I just get an LT4 module?

http://shbox.com/1/1995_pcm2.jpg

According to Freescan I am registering knocks and it does occasionally retard the timing so is the sensor working? I don't get it....

test proceedure is here:

http://shbox.com/1/4th_gen_tech2.html#knock_sensor

 

On the air pump code I am not sure what to do to clear this code, I do not have the relay or fuse wiring left for this circuit. I guess the PCM senses the coil resistance of the relay?? Other forums say just put the relay and fuse back in and the code will clear but I eliminated all that wiring so can I just measure the relay coil impedance and just put a resistor on that pin?

 

See pin A14 in the diagram

http://shbox.com/1/1995_pcm4.jpg

 

SO I have the SES light on and the fan runs constantly but according to Freescan it does go from open loop to closed loop the temp is usually around 178 and I have a 160 thermostat

 

Will my fan operate normally when I get rid of the SES light trouble codes?

 

I am almost there I am so close to driving this on the street!

 

I think my Mallory fuel pump may be acting up, I already had it sent back to Mallory once already, it is LOUD and sometimes sounds funny and fluctuates pressure.

Is everybody else running one of those Walbro pumps?

My Mallory is an -8AN but all my lines are -6AN what size is the Walbro units and what model should I order?

Thanks,

Greg

[deja]

You might want to cleanout the fuel rails too. When I tore apart the assembly that would not allow my LT1 to start I found 6 of the injectors did not work and there was so much crud in the rails I was shocked. This assembly had sat for at least 1 1/2 years. You can disassemble the rails pretty easily. Just DO NOT attempt to remove the return line (the one with the purge valve) from the passenger rail, it is glued in. The short one on the front will pull out of both rails and has o-rings you can get at the auto parts store. I also pulled the regulator and the screen had crude on it too. I am going to replace that too. I ended up getting 8 rebuilt Blue Demon injectors from http://fuelinjectorconnection.com/shop/index.php?_a=viewProd&productId=55. They are local to me and were recommended by some friends that have dealt with them. I got them in 2 days.

[gvincent]

Well it is still running and I replaced the 2 injectors and that was problem #1 solved.

Problem #2 was the code #29, went into TunerCAT and turned off the air pump and that took care of Problem #2

Problem #3 was code #43 the knock sensor, I followed the Shoebox test proceedure I posted earlier for the knock sensor and did not have the 5 volts, so traced it back to the PCM Pin D22 (Blue D connector dark blue wire on Pin 22) well I discovered I was 1 pin off and had used the dark blue on pin 23 which went for the AC. Swapped the wire and for the first time with both LT1 engines I no longer had any trouble codes and the SEL light was OFF, YEAH!!!

 

EXCEPT here is where the 1 step backwards comes in, my fan no longer turns on!!!!

Now the fan was always constantly running when the SEL light was on which is what it was supposed to do from what I have read so it is working. When I read the PCM or Program the PCM with TunerCAT the fan kicks on for a second at the beginning and end of each read or program, so I am thinking I must have it wired right and it must be a setting in TunerCAT that I need to change somewhere.

When the SEL light was on and the fan was running I never got above 178 degrees and I have a 160 thermostat which was correct I suppose.

Well I have looked at the Tables in TunerCAT to see what my fan settings are at and couldn't find the same tables that are referenced in this thread:

http://forums.hybridz.org/showthread.php?t=124211&highlight=Fan+settings

which was posted by 80LT1

The part about setting the fan settings was:

Fan thresholds:

These are the engine coolant temperatures that the ECM must see in order to kick the fans on. For the stock 180* thermostat the fan turn on points are 226 for the low speed and 235 for the high speed. A good starting point for either the stock or an aftermarket 160* thermostat is to set the low speed fan to come on 20* after the thermostat has opened, and the high speed to come on 6-8* after the low speed. It is best to experiment and see what you‘re car likes best. Use the Fan 1 On Threshold (Low MPH) and the Fan 2 On Threshold (Low MPH) for your turn on temperatures.

The Fan Threshold High Speed (MPH) allows you to give the computer a mph value to distinguish between the high and low speed fan turn on points. This gets pretty interesting.

For example, you drive a lot in stop and go traffic and are consistently driving at 35mph and under. You can set your high speed threshold to 35mph and then at every speed under that the low mph fan turn on temps are active, and at any speed higher than that the high mph fan turn on temps are active. That way you can kick the fans on earlier at lower speeds to make up for the lack of airflow coming across the radiator while you‘re sitting in traffic. Then once your at a speed that allows the radiator to see more airflow the high speed turn on temps take control.

 

Fan Hysteresis Low/High Speed: These values are the temperature changes that will turn the fans off. If you’ve set the hysteresis to 3, then the fans will not turn off until the coolant temperature is 3 degrees cooler than the fans turn on point.

 

Fan control turn-on points based on oil temp are not used in our ECM’s since it takes no input of oil temp.

 

There are also values for fan turn-ons based on A/C pressure. I have not messed with these values as I don‘t see an advantage to it.

 

Now I could not find the settings in the tables I have highlighted in Red above anywhere at least not worded the exact same way anywhere?

 

Am I looking in the right place?

What fan settings should I put in there and where? What Table?

Shouldn't the fans come on anyway? I let it get up to 210 degrees and still no fan turn on so I shut it down for fear of overheating and blowing a head gasket on motor #2

 

ARGHHH!

I will look at TunerCAT again tomorrow night and write down all my settings from the first 2 table categories, maybe some of you LT1 guys with TunerCAT can compare my PCM settings with yours.

 

I am so close DAMMIT, I registered and insured it as an antique last wednesday and have to have it safety inspected and appraised in 10 days

 

Please help!

Thanks,

Greg

[jbc3]

I have mine set for coolant temp 170/185 for the 1st fan and 185/195 for the second fan.

The Hysteresis I left stock.

(LT1-edit numbers)

 

I will PM you a file that I did for another HybridZ with these numbers in it.

 

Jody

[gvincent]

Thanks Jody,

I also got your email and PM, I will copy the .bin file and bring it home on a CD, as the old PC laptop I have does not have a USB port or a working network port but does have a working CD rom reader. I only use it because of the serial port, All i have on it is XP Pro TunerCat, FreeScan, and PCM Communicator.

So just direct TunerCAT to open the .bin file and then have it load the program to the PCM?

I am very new and ignorant to computer controlled engines obviously.

Thanks,

Greg

[jbc3]

Take a look at the file in TC to give you an idea what the settings are.

That file has WOT blocker (prevents the low RPM block learns to effect the WOT fuel supply) This is also an automatic tranny file with performance shift, 6400 rev limit, 215-50-17 tires, 3.70 rear and raised RPM and block learn settings. Then the lower fan settings. EGR/CCP off. If you want help, e-mail me your file base file and let me know what changes and mods you have.

[gvincent]

Thanks Jody I will, I had hoped to check it tonight but here I am working late at work again.

I will definately take a look. and will check my settings VS yours.

I will send you my file base for you to take a look.

The current motor is a completely stock 95 LT1 from a Caddy Fleetwood with the iron heads and the T56 manual from the original 95 Firebird Trans Am LT1 which has a rod knock , I only have the Sanderson headers and a cold air intake system, MSD Opti and blaster coil. Modified fuel rails with AN fittings and an Aeromotive AFPR I am using an Autogauge electronic speedo and tach, although I haven't driven the car far enough yet to setup the speedo and see if I have the VSS signal correct.

I really appreciate your offer to help, after 3 years I am so close to actually driving this car further than my driveway and around the block. I was at this point last summer when the Firebird LT1 developed a knock while still on jackstands

Thanks again,

Greg

[deja]

Listen to the man Greg. That other Z he is talking about to is mine.

[gvincent]

The Fan is running!

Dale your right, Jody is Da Man!

After several emails and swapping a few files back and forth the fans started working, Both Jody and I couldn't pinpoint what did the trick but it works now.

I am going to follow Jody's advice and learn more about tuning and visit the websites he directed me to.

If anybody is interested I have both the before and after TunerCAT files and will be happy to share the files and emails between Jody and I which helped to narrow down the problem. Now swap out my expensive leaking Mallory fuel pump and I can take it for a real drive.

Yahoo!

Thank you Jody and all who helped.

Greg

[deja]

Cool. Keep an eye on the temp gauge and the coolent level. It took a couple cool downs to get mine completely full and the temp consistent. Damn the LT1 reverse cooling, LOL.

[Bartman]

Man Jody is a very helpful guy. He was a big help with issues on my LT1 as well. Hope everything works out well for you now gvincent.

[gvincent]

Cool. Keep an eye on the temp gauge and the coolent level. It took a couple cool downs to get mine completely full and the temp consistent. Damn the LT1 reverse cooling, LOL.

 

Thanks Dale,

Yeah I was keeping an eye on the levels and checking the two bleed screws and all is well.

But in keeping with my two steps forward and one step back tradition on this project I now have a leaking heater valve I think.

 

I started putting the dash center and console in as I now have all working gauges again when I thought I would free up the stuck cold/hot slider up so it would work, well i got it working alright still a little stiff but works if you don't move it fast or you will bend the cable. Well I started it back up again to make sure all my gauges were still working after putting the dash back together and I smell AntiFreeze, I had just put the carpeting back also, antifreeze is dripping under the passenger side of the car from the drain hole in the floor.

I think the valve is leaking as it wasn't leaking before I messed with the control cable. This is not going to stop me! I just connected the heater hoses together with a short piece of pipe and some hose clamps for now, I am going to drive this thing on an actual road if it kills me! I'll figure out how to remove and replace the valve later this winter.

[gvincent]

Thanks Bartman,

 

Yeah, Jody is a great help, I am now obsessed with getting to drive this car, after 3 years, 2 motors, lots of money and work, and now registering and insuring it two weeks ago I WILL get some enjoyment from driving it before it snows or I'll kill myself trying.

Thanks,

Greg

[mark]

Just don't wad the car up on the test drive