code 44

[GsxEcutioner]

Hey everyone, I have had this problem for the longest time, I have a code 44 (ignition Coil) that keeps coming on then shutting off. Well I swapped out my coil packs for a set my friend had, and then it was fine but on the way home it messed up again, I changed it again today and still the same problem. Any Ideas?
-Shane

 

[steve]

Other possible causes are power transistor, harness, and ECU.

 

[GsxEcutioner]

power Transistor???? 0_o, uhm I was thinking the ECU could cause this but I wasn't sure.

 

[steve]

Yes, power transistor module since it drives the coil.

The FSM checklist order is harness, ignition coil, power transistor. The 1GTM says that a 44 is a open in either of the ignition coil circuits. The factory didn't know that the caps would leak so they left the ECU off the list, I'd put it second on the list of things to check.

What the 1G ECU is actually doing is looking at the the Ignition Pulse Detect signal from either the tach module on the bottom of a 90 style coil or the from the PTM on the later cars to see if it's toggling. Once the ECU thinks that it's missed 20 ignition events it flags the CEL.

The Ignition Pulse Detect (tach) signal is the gated (OR or NOR depending on which style) output of the two coil drive signals from the PTM. It's the same signal that drives the gauge cluster tachometer. The ECU's RPM reference is the CAS.

When the ECU charges the coil it pulls it's side of the primary low with the PTM. The Ignition Pulse Detect will reflect the voltage change back to the ECU. When the ECU fires the coil it switches off the PTM which turns off the coil current in the primary but causes the voltage at the PTM output to rise, spike and then settle back to battery voltage until the next time the ECU charges the coil.

So this senses an open coil primary or bad power transistor output but the outbound wiring from the ECU to drive the coil, the wiring from the PTM to the coil, the power to the coil, and the wiring for the Ignition Pulse Detect to the ECU can all be bad or loose and trip this error. Then it possible for the ECU it's self to be damaged. The circuit in the ECU is close to the capacitors that leak.

 

[GsxEcutioner]

it came back, so im going to change my ECU asap.

 

[GsxEcutioner]

it only happens in low rpms too....2-3k

 

[bling5tatus]

I've had a code 44 on my car for I don't know how long now... my ecu was capped and showed no signs of damage when it was capped.... the coil pack and the module have both been changed more than once... so i'm suspecting possible a harness problem... I dunno.

I seem to remember 44 saying that it was an inj circuit malfunction... maybe i'm crazy.

 

[ramsack]

my '91 car has been skipping lately, and today it did it really bad and the tach acted weird after that. it threw code 44 also. is this more likely the power transistor than the coils?

 

[GsxEcutioner]

wow, you brought my thread back after a year , i was looking at new post and saw my post, and thought "Hey i havent posted in awhile, wtf!?" aha, For me, it wasnt anything other than my ECU taking a crap. Its actually happening again now with my eprom ecu, so im going to check my caps.
-shane