1993 945T around 173k miles.

Car all of a sudden lost much power on highway, Check Engine light came on, and it was only able to maintain 20mph speed. Pulled over and waited about 30 minutes. Car then started right up. I shut it down before pulling code in Mode 1. Socket 2 gave 1-1-1, but socket 6 gave 1-4-4. Check the code table and it says:

- 1-4-4*
- No load signal from fuel injection system
- Faulty wiring from LH to EZK; bad LH module 
- Engine lacks power; stalls; doesn't start or is jerky

Elsewhere in the 7xx/9xx FAQ I found this:

"These same symptoms, though, can also be caused by a defective fuel pressure regulator, a plugged fuel filter, dirty fuel injectors, a restriction in the fuel supply line, a leaky pump check valve,  or a dirty filter sock in the tank."

I think the fuel filter must be changed first. Haven't done that since I bought the car used. My question is: "Am I on the right track?"

Much thanks,
Lih-Yen

Calling the list for help again; 1993 945T around 173k miles. Please see my post yesterday, subject '1993 945T: Fault code 144'.

I had the garage replace the fuel filter (not throwing parts at the car; the filter is loooong overdue) and timing belt and tensioner (ditto.) The mechanic noticed what appeared to be moisture condensation inside the distributor cap.

The car was then driven about 40 highway miles fine. However, near the end of the trip the engine stalled once, Check Engine light went on, but started up again right away, and there did not seem to be a loss of power. I pulled the following fault codes: 3-1-2 (socket A2) and 1-4-4 again (socket A6).

Code 1-4-4*:
- No load signal from fuel injection system
- Faulty wiring from LH to EZK; bad LH module 
- Engine lacks power; stalls; doesn't start or is jerky

Code 3-1-2:
- Signal missing for knock-related fuel enrichment
- Wiring break between EZK terminal 4 and FI #28
- No faults evident

Recent history: About two weeks ago the engine slightly overheated due to a massive coolant loss because one of the radiator side tank developed a crack (Nissens.) OBD gave codes 1-2-3 (ECT signal missing, to/from), 2-2-4 (ECT signal missing/faulty), and 3-1-2. Replaced the radiator, cleared codes, and had logged about 1000 miles without inceidence until yesterday.

My questions are:
1. What exactly does it mean by "No load signal"?
2. Where are the components (for what matter, connectors)?

Please help, this is my better half's daily driver. I consider myself handy, and have access to meters and scopes (if that help), but don't have tons of time at hand. If there do no seem to be straightforward diagnostic procedures/fixes I will have to take it to a Volvo garage.

Much TIA,
Lih-Yen

My questions are:
1. What exactly does it mean by "No load signal"?
2. Where are the components (for what matter, connectors)?

1) Per Regina/Rex Manual: "In the partial load range, a load signal test is carried out twice per engine revolution.
If the load signal is constantly high or low, fault code 144 is set.

2) The path is (yellow wire) from FI ECU pin 25, to Conn.55 pin 2, to Conn. 50 pin 7, to Ign. ECU pin 8.

FI ECU is forward of front right door
C55 is near firewall under Right strut brace.
C50 appears to be in same area on the Left side.
Ign ECU is above accellerator pedal
--
Bruce Young,
940-NA (current)
'80 GLE V8 (Now gone)
'83 Turbo 245
'73 142 (98K)
'71 144 (track modified--and going to be crushed unless...)
New 144 from '67 to '78
Used '62 122 from '63 to '67

From the FAQ:

"These same symptoms, though, can also be caused by a defective fuel pressure regulator, a plugged fuel filter, dirty fuel injectors, a restriction in the fuel supply line, a leaky pump check valve,  or a dirty filter sock in the tank."

I think the FAQ is saying these parts can cause the same *Symptoms" but NOT the 144 code. The code is most likely based on a signal failure, which in turn can result in various symptoms.

In other words, I wouldn't start right off by throwing parts at it.
--
Bruce Young,
940-NA (current)
'80 GLE V8 (Now gone)
'83 Turbo 245
'73 142 (98K)
'71 144 (track modified--and going to be crushed unless...)
New 144 from '67 to '78
Used '62 122 from '63 to '67

Thanks for the insights.

A new fuel filter did go in, as the old one had at least
80 thousand miles on it. The car started up fine now.
The mechanic also checked and found the distributor cap
was 'wet' inside and asked if I sprayed it with anything.
Need to clarify with him as to what fluid he thinks
the wettness was caused by.

I did wiggle all the connectors in sight and none was
obviously loose. I think '91 and later 9XX's got upgraded
electrical wiring througout. I will keep an eye on that.

Lih-Yen

Check the connections at the Air Mass Meter. Could be a loose pin in the connector, or the connector is not fully plugged in. Don't plug it in or unplug it with the key "ON". Some people have succesfully squeezed the sockets a little to make better contact with the AMM pins.
--
Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K

Thanks.

The meter multiplug checked out. Pins are clean and the connector securely connected.

BTW, why has the AMM connector anything to do with code 144?

Lih-Yen

There is a Service Bulliten on code 144 saying in part: "poor soldering on Fuel Injection System relay output 87-1 can produce an intermittent open-circuit ...to Pin 9 in the... (then a typo, but trust me, they mean Pin 9 of the Fuel Injection Control Unit .)

You can find relay locations and relay soldering procedures in the 700/900 FAQ.

I have also heard of poor connections in the "crimp terminal" where the wires plug into the relay socket. (Not a happy thought)
--
Bruce Young,
940-NA (current)
'80 GLE V8 (Now gone)
'83 Turbo 245
'73 142 (98K)
'71 144 (track modified--and going to be crushed unless...)
New 144 from '67 to '78
Used '62 122 from '63 to '67

Bruce,

Thanks very much for the timely info. Your replies are succinct and, just like your user name, Lucid.

I will report back when I resolve this issue.

Gratefully,
Lih-Yen

Bruce,

I took the FI relay out and inspected all the solder joints using a magnifying glass. Sure enough I found some very fine cracks and solder crystalination. I also found the relay contact surfaces were somewhat pitted. I carefully resolder all the joints and put it back. Time only will tell if this is a succesful repair.

If and when I get time I will look into this relay construction a little closer (maybe not, depend if the car acts up again, and my time.) These solder joints and circuit board traces for pin 87-1 don't seem to be the only conductive path, not the main one at least. The very heavy copper bar and the other metal frame alone seem to be much more capable of carrying the current. This is what I found which appear to be the copper bar current path:

Pin30 - bar - metal frame - contact - contact - metal fram bar - pin 87-1. Maybe I missed something.

Thanks for the help again,
Lih-Yen