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240 '85 B230F fuel cut in 1st gear

Did you see photo I posted?

At 1500 RPM, remove vacuum line, and stick your tongue on it...does it suck?

Using timing light, at 1500 RPM, remove vacuum line, does timing change?

I over looked that!

I set the timing to ~12 degrees advanced, with the gun set to 0. I followed the instructions in the photo and the timing did not change with the vacuum line removed. When I removed it I did cap off the vacuum line, not sure if that makes a difference or not. The vacuum line to the ignition module does have suction.
 
timing did not change with the vacuum line removed.

Question is was the same vacuum at ignition module as there was at its source (aka intake manifold)? In other words, is the vacuum line from intake to ignition module "fit for duty."

One more option...if a hand held vacuum pump can be hooked directly into ignition module's vacuum port, you could test once more.

Without vacuum being "read" by ignition module, you got no timing advance when you put peddle to the metal, which is needed for vroom. Further, if the Chrysler box (ignition module) is "talking" to LH 2.2, then LH 2.2 will not increase the fuel amounts.

Double check....make sure you had enough vacuum to activate ignition module.
 
Will do! Thank you very much for your help so far!!

I will need to pick up a vacuum pump tester and pressure gauge to test everything.
 
vacuum pump tester

An auto supply might have a brake bleeder kit that is loaned out, which might have a hand held vacuum pump.

A vacuum gauge can measure the fitness of vacuum line from intake to IGN-MOD, when measured at both ends...two tests, one at intake, and the other and end of vacuum line.

Information about timing advance....for a distributor setup....which is similar to your setup.

"At part throttle, high manifold vacuum moves the diaphragm in the vacuum advance canister on the distributor to add more timing. But at WOT, the vacuum drops to near zero and vacuum advance is removed and the total timing then is established by the initial plus the mechanical advance.Mar 27, 2015"

https://www.onallcylinders.com/2015...rstanding-vacuum-advance-and-why-you-need-it/
 
I grabbed the tester and gauge on Amazon last night so I'll have them here this weekend. I figured I might as well keep them for future use.

A vacuum gauge can measure the fitness of vacuum line from intake to IGN-MOD, when measured at both ends...two tests, one at intake, and the other and end of vacuum line.

That is my exact plan for the gauge.

Thanks for the info on timing advance, I'll give that page a read.
 
I'd have to visually look, but on throttle body, there may be two ports...one for emission, and the other for IGN-MOD. When engine is at base idle, there should not be a vacuum on IGN-MOD's port on throttle body.

IIRC, from years ago, on distributor based engines, when doing timing, pulling vacuum line off was a prudent measure...so timing was set with no vacuum going to distributor (or IGN-MOD).

I've not examined vacuum ports on throttle body, but I assume the emission port gets vacuum when engine starts up. It's function is to suck gas fumes from charcoal canister.

Hence, each vacuum port may "suck" differently.
 
I was able to get everything tested this weekend. I put the vacuum pump on the Ignition Module and it held 15in Hg without loosing any pressure. I also noticed a cracked line on the vacuum pump for the cruise control so I fixed that.

Vacuum at Intake Manifold
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Vacuum at Ignition Module
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The vacuum line for the Ignition Module is located on the intake manifold on my car. The throttle body has both ports used by the charcoal canister. I've noticed it's that way on friend's 240 as well. The line itself doesn't seem to have enough length to get to the throttle body.

MIwsuKOl.jpg


I am hearing what sounds like a rushing of air in near the head next to the fuel rail. I'm not sure if this is just the sound of fuel rushing through the rail or if I have a leak somewhere. I checked all the lines and they seem good, I also sprayed some starter fluid around everything to check for leaks. I am going to pull the breather box out and inspect it. Video for sound reference below.

<iframe width="560" height="315" src="https://www.youtube.com/embed/txQRd_WWeK8?controls=0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
I picked up an Ignition Module from a board member and it didn't seem resolve the cut out issue. I have not checked yet to see if the timing advance is working with this Ignition Module. I will look up how to test the knock sensor.

When the weather gets a little cooler I'll get back to working on the car.
 
I noticed that with the timing set to 15 degrees or higher there is still a cutout but the return to normal is much quicker, only drops about 300rpm. With it below 15 degrees the car cuts out at 2000rpm, like "normal", then drops to ~1000 rpm before it runs to normal.

I checked the wiring on the knock sensor and in doing so I noticed the spade on the knock sensor moves around when touched... One would assume that's not normal. I took a picture of the sensor and it looks like the soldering has broken up.

I am going to grab the knock sensor from a LH 2.2 240 wagon that's at the yard, tomorrow or Sunday. It seems the LH 2.2 knock sensors are hard to come by new.

 
...knock sensor...spade on the knock sensor moves around..

1985 LH 2.2's knock sensor was specific to Vehicle Fitment: Volvo: 242 1983-84 | 244 1983-88 | 245 1983-88. ...Volvo 1317296...$125.00 @ IPD

Cross Reference - Doing quick searches, STANDARD MOTOR KS82 comes up at $150.00 price range.

I suspect someone got "physical" with your knock sensor...two hands should have been used...one to hold spade down, while other to remove terminal.
 
So I replaced the knock sensor and nothing has changed... but I had a feeling that was going to be the case.

I set the timing back to factory and noticed that if I start up the car and rev it up so it cuts out and then set timing, once I turn off the car and start it up the timing is lower than what it was previously set at. Not sure if this is due to the cut out or just from me reving the car up and letting it idle before adjusting timing.

Still have not checked fuel pressure, I have been lagging on getting the testing equipment from a friend. I am going to try and get that done ASAP.
 
...timing back to factory...turn off the car and start it up the timing is lower than what it was previously set at.....

Timing would be controlled via Chrysler Box....I'd have to review its pin-out, but if it is "aware" of engine temperature, this can change timing, or if LH 2.2 is "talking" to it.

Timing is suppose to be done with engine warm, as explained in TP 30432/2; here's a snapshot of instructions.

Older vehicles with a vacuum and mechanical advance, timing is changed by changes in vacuum and changes in RPM. Chrysler Box is doing both also, electronically. Google that TP, and look at charts
 
Never owned a vehicle with LH 2.2, but on schematic, the throttle position sensor (TPS) switch has a wire for "Idle Speed Adjustment Point." TPS does have a wire going to Chrysler box.

SEE: Setting Base Idle Specs and Mixture on Bosch LH2.2-Equipped Cars.

Needless to say, TPS must be set correctly. A tach is required to set idle correctly

Thanks! I ordered some led diodes so I can make the tool needed so set the base idle after checking the O2 sensor.
 
"You don't really need the 750 ohm resistor, and its value certainly isn't critical to the function; just protects the LED if you drop the ECU end of the probe on a ground."
 
"You don't really need the 750 ohm resistor, and its value certainly isn't critical to the function; just protects the LED if you drop the ECU end of the probe on a ground."

I didn't bother to order the resistors after reading that. I ordered a pack of 100 led diodes so I should be good. I will just have to figure out what to use all the extra led lights on :thinking:
 
So I finally got the fuel pressure measured. Not sure if the idle pressure is within spec I will try to find a manual to get that information. All I did to when checking is hook up the gauge to the car and let it idle up to temp. I did check the fuel pressure when the car cuts out and it did not budge.

I also checked the voltage on the O2 sensor and it appears to be cycling within spec. I noticed that when I rev up the motor and it does the cut out the voltage on the O2 sensor drops to 0.00. I will try adjusting the AMM this weekend following that guide.

Fuel pressure at Idle
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Fuel pressure with FPR unplugged
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Fuel pressure after a few minutes of the car being turned off
bagaIcml.jpg
 
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