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Engine Running Issue

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UPDATE;

 

I replaced the IAC valve with one from Lotus. It was larger than the one Michael's mechanic replaced and it fell apart when I removed it ( the pintle fell off) both have 2 angles. Once the ECU learned the new IAC the rpm dropped to 1200 and then bounce back to 1500. It's like the ECU was dropping the rpm for a few seconds, so I figured someone might have raised the idle adjustment up. I took a mirror and looked into the idle stop cavity and it was scratched up, looks like scratches from a screw driver. I used a 1/4 drive rachet, 1/4 socket, and a standard bit and turned the screw in 1/4 increments, each1/4 turn is about 100  rpm. 1 and 1/4 turns brought the rpm down to around 1000. No stall or stumble when the gas petal is pressed. The engine sounds much better. When cold it idles between 2000 and 2500 rpm, as it warms up it gradually drops to 1000 rpm. Michael put in a ign module from a baretta,

Thanks for everybody's help. 

 

Does anyone have a stock ign module for sale???

 

Problems on the agenda;

Stiff brakes- getting vacuum to the booster

Fans only work with A/C on.

Engine speed missing

I probably missed something

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THECARREAPER on LotusTalk lists the Isuzu 8104683430 ignition module as being a compatible replacement.

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THECARREAPER on LotusTalk lists the Isuzu 8104683430 ignition module as being a compatible replacement.

Thank you. Michael gave me a spare ign module when I bought the 89 Esprit from him. I think he said one was from a Baretta and the other was from a Isuzu. I think he said the module that is in the car runs the best, but the other one will work. Espritmon and Freescan  cannot detect the engine speed with either module.

 

I would like to find a Esprit ing module. If anyone has one for sale Please let me know.

I also have a 1990 Esprit, that I will keep.

I would like to buy a 1995 Esprit.

Thank you

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UPDATE;

 

I replaced the IAC valve with one from Lotus. It was larger than the one Michael's mechanic replaced and it fell apart when I removed it ( the pintle fell off) both have 2 angles. Once the ECU learned the new IAC the rpm dropped to 1200 and then bounce back to 1500. It's like the ECU was dropping the rpm for a few seconds, so I figured someone might have raised the idle adjustment up. I took a mirror and looked into the idle stop cavity and it was scratched up, looks like scratches from a screw driver. I used a 1/4 drive rachet, 1/4 socket, and a standard bit and turned the screw in 1/4 increments, each1/4 turn is about 100  rpm. 1 and 1/4 turns brought the rpm down to around 1000. No stall or stumble when the gas petal is pressed. The engine sounds much better. When cold it idles between 2000 and 2500 rpm, as it warms up it gradually drops to 1000 rpm. Michael put in a ign module from a baretta,

Thanks for everybody's help. 

 

Does anyone have a stock ign module for sale???

 

Problems on the agenda;

Stiff brakes- getting vacuum to the booster

Fans only work with A/C on.

Engine speed missing

I probably missed something

 

It's good that you got it working better, and to a stable idle, but you really need to adjust the minimum air rate bleed screw while connected to freescan, since the IAC counts have to be between 20-40 for best results at idle with a warm engine.

 

You can't adjust the "idle screw" (minimum air rate bleed screw) by ear, as the IAC will constantly fight to keep the idle at the desire RPMs.


Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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What are the part numbers on the ignition modules you have?

Looks like a Airtex # 6H1131  and the other module is a 1085J07

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It's good that you got it working better, and to a stable idle, but you really need to adjust the minimum air rate bleed screw while connected to freescan, since the IAC counts have to be between 20-40 for best results at idle with a warm engine.

 

You can't adjust the "idle screw" (minimum air rate bleed screw) by ear, as the IAC will constantly fight to keep the idle at the desire RPMs.

I found a step in one of the 3 Lotus service notes. It said you should never have to adjust the idle stop unless someone has tampered with it, but if you do then use 1/8 increments. It also said try not to go over 1 full turn. I stopped the engine then made the 1/4 increments, started the engine, observed the rpm change in Freescan. The IAC starts at 170 and  then it starts counting down to 5 then back to 170 and starts counting down again. On one cold start it started at 240 then jumped to 145 then started counting down. A/F started at 12.1 and slowly raised to 14.6 when the car was at running temp.

Thank you

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I found a step in one of the 3 Lotus service notes. It said you should never have to adjust the idle stop unless someone has tampered with it, but if you do then use 1/8 increments. It also said try not to go over 1 full turn. I stopped the engine then made the 1/4 increments, started the engine, observed the rpm change in Freescan. The IAC starts at 170 and  then it starts counting down to 5 then back to 170 and starts counting down again. On one cold start it started at 240 then jumped to 145 then started counting down. A/F started at 12.1 and slowly raised to 14.6 when the car was at running temp.

Thank you

 

Yea, that's not following the process.

The proper process in in EMH section (EMH.3 page 17).

 

The manual is partially correct that you should never "have" to do this, but the problem is when "shade tree mechanics" decide to "adjust" the idle speed by ear.  It is also an issue that air leaks in the intake manifold may cause problems with this minimum air rate bleed and the IAC.  Any problem with IAC counts at idle when the engine is warm, or stalling, should begin with verifying that there are no air leaks in the manifold.

 

However, it also appears that after 20+ years, the minimum air rate bleed screw does occasionally need to be adjusted.

 

It is imperative to do the correct procedure, after air leaks are ruled out:

1) connect freescan

2) start engine  AC and all electrics off.

3) let it idle up to 82C coolant temp, and closed loop, DO NOT touch the gas pedal!

4) watch IAC counts stabilize in freescan.  They should be between 20-40.

 

If counts in step 4 are too low, check for intake air (vacuum) leaks at
hoses, throttle body and intake manifold, or damaged throttle lever, and correct
asnecessary. Also refer to Code 35 and associated 'Diagnostic Aids' in section
EMH.4.
If no vacuum leaks or other causes of excessive air into the intake are
found, refer to the 'Throttle Plate Stop Screw (minimum air rate) adjustment
Procedure' below.
If counts in step 5 are too high, check for damaged throttle lever or airflow
restriction by the throttle plate. If no problem is evident, remove intake
plenum cover and clean residue from inside of throttle body bores and from edges of throttle plates.
Use a lint free cloth with a suitable cleaner such as AC
Delco Carburettor Tune-Up Conditioner or equivalent. Do not use solvents
containing rnathyl ethyl ketone. Re-check IAC valve counts, per the preceding
procedure. If counts are still too high, refer to 'Throttle Plate Stop Screw
(Minimum Air Rate) Adjustment Procedure

 

5) engine idling, carefully adjust the minimum air rate bleed screw (not the throttle body balance screw!!!!) while watching the IAC counts in freescan. Carefully adjust the  screw in tiny tiny increments (~1/16th of a turn) at a time and allow the IAC counts in freescan to stabilize. 

6) continue adjusting until the IAC is between 20-40 and STABLE while the engine is at idle and fully warmed (82C)

 
More throttle plate opening = lower IAC valve counts
less throttle plate opening = higher IAC valve counts
 
If it is necessary to change the adjustment more than one turn either way,
other causes of incorrect idle speed should be investigated as described above.
Ensure that the anti-tamper plug is refitted after any adjustment.
 
BTW the A:F reading in Freescan is "Desired A:F", desired by the ECU, it has no relation to actual measured A:F.
 
IF your IAC counts are not between 20-40 at idle with a warm engine, then you WILL have drivability issues.  You cannot adjust it by ear!

Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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Googling the Airtec 6H1131 shows it coming up as a xref to the Isuzu 8104683430 ignition module but I'm not 100% convinced. The pinout of the Airtec 6H1131 is here http://www.airtexve.com/custom_searches/showpinoutdiagram.php?partno=6H1131and it's the 3 pin connector that I'm wondering about. I would have thought pins B and C would be reversed if it were to suit the Esprit ecu as it doesn't seem correct to leave the VRS negative pin floating :huh:  That said, the ecu must be getting a signal or the engine wouldn't run at all.

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A Big Thank You to everyone!!

 

The car is running great now.

If I didn't have the 1990 Esprit I would keep the 1989, but I want a V8 Esprit, so it's time for this little piggy to go to the market.

 

I've tried to find a used ign module, so it will stop throwing the 41 code.

 

If anyone has the correct ign module, Please let me know  

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Well done! Although, it might have been a good idea not to announce the sale in the same message thread, especially with some still (?) unresolved problems )))

Problems on the agenda;

Stiff brakes- getting vacuum to the booster

Fans only work with A/C on.

Engine speed missing

I probably missed something

.... and the possible Code 26's

Cheers

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Dave "Changes" probably has a stock ing module available.

i will once the weather cools enough for me to finish my ECU conversion.

if i remember correctly, the VR sensor on the flywheel for engine speed is connected to the ign module;  the ign module reports engine speed to the ECU.


chris

90SE

just because I don't CARE doesn't mean I don't UNDERDSTAND

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Well done! Although, it might have been a good idea not to announce the sale in the same message thread, especially with some still (?) unresolved problems )))

.... and the possible Code 26's

Cheers

Code 41  is the only major issue. Code 26 only pops up every now and then. Sometimes its gone for a week. The vacuum is ok. Art B suggested to check the pads for debris, since the car sat around so much.  I then noticed the rotors were a little rusty, pulled the pads and cleaned the rust of them they are ok now.

I wanted to replace the front pads, but in Arts paperwork it stated  only (wildwood brake kit 1528.00 dollars) they still have some life left. I still have  close to a full petal.  I went online  found wildwood, they make more different pads than carter makes pills.

The new owner needs something to do to get familiar with the car. I know it will offset the price. I want the new owners  to know what they are getting into.

Thanks for all your help

 

Tommy

Dave "Changes" probably has a stock ing module available.

i will once the weather cools enough for me to finish my ECU conversion.

if i remember correctly, the VR sensor on the flywheel for engine speed is connected to the ign module;  the ign module reports engine speed to the ECU.

Thank you, I will be waiting to hear from you. 

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Code 41  is the only major issue. Code 26 only pops up every now and then. Sometimes its gone for a week. The vacuum is ok. Art B suggested to check the pads for debris, since the car sat around so much.  I then noticed the rotors were a little rusty, pulled the pads and cleaned the rust of them they are ok now.

I wanted to replace the front pads, but in Arts paperwork it stated  only (wildwood brake kit 1528.00 dollars) they still have some life left. I still have  close to a full petal.  I went online  found wildwood, they make more different pads than carter makes pills.

The new owner needs something to do to get familiar with the car. I know it will offset the price. I want the new owners  to know what they are getting into.

Thanks for all your help

 

Tommy

Thank you, I will be waiting to hear from you. 

I wanted to get both, but Dave sold his awhile back, so It's all up to you now. I hope it cools down.

Thank you

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it doesnt get cool here lately until Nov Dec!

it seems i have a following anxiously awaiting the completion of the conversion...


chris

90SE

just because I don't CARE doesn't mean I don't UNDERDSTAND

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it doesnt get cool here lately until Nov Dec!

it seems i have a following anxiously awaiting the completion of the conversion...

Ok, just let me know when you're ready 

Thank you

Tommy

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