Hi, this is my first post as I am a new member.
Firstly, let me just say what a great Forum. I have learnt a great deal. Used to be on the tools, but a long time ago, never got to work on EFI & electronics etc., so have to re-educate myself.

My daughter drives my old car, a 9/92 TR magna 2.6 EFI 5 spd sedan. I bought it in 2010 with 99,000 km. It now has 140,000 km. I service it every 5,000 km. Over a period of 6 months or so, the car has given the impression that it is missing under load between 1,000 & 2,000 rpm or between 60 & 80 km/h.

At first I thought it might be a bad plug. I always use Bosch. Spark is good, cleaned & reset. Changed what I believed to be original Mitsi leads to Bosch. Dissy cap, Bosch dated 1992 changed for another Bosch last Sunday brand new dated 3/95 !!!!

New rotor button......Bosch. Cleaned throttle body, removed all air cleaner tubing etc. removed & cleaned MAF sensor. Cleaned ALL electrical connectors. Car idles perfectly at 850 rpm. After 2,000 rpm, engine smooth as. Checked resistance of coil.......ok.

I tried to check timing, but I think I might have come unstuck there compared to what I have been used to pre - electronics !

I am now thinking injectors, but if they were faulty the "miss" would be there at other rev ranges ????. Car does not use Ethanol fuel, only 91 Mobil & sometimes 95 Mobil from 7 Eleven. Oil is 20w 50 Penrite.

I think I have covered everything, have I missed anything in my diagnosis ?

Any thoughts greatly appreciated.
With thanks.

Have you checked the dizzy and TPS plugs (black straight 4pin connector)? The wires usually breaks at the terminals and the pins on the sensor usually have oxidize

Checked resistance of coil.......ok.

Yep. With a multimeter, I suppose? Doesn't work, you can get good readings but under high voltage it may still be breaking down. Biggest load on the HT circuit is under low rpm load.
Ignition timing: Short the advance cut, should be at 5 degrees BTDC. Remove short, check it is at about 13 degrees.

Thanks guys........yeah, I was thinking coil even though I did get a reading.

I don't understand about shorting some wire to check timing.
Can u explain that to me please. I have timing light with connector for plug lead and + & - leads for battery.

What lead goes where ? Black to earth & red to + on battery & connector to No. 1 lead ?

I did read it is up near the firewall somewhere.

can be the maf -.............

if it isn't coil or that dissy plug in point

-an engine will hesitate under load -if the Air flow meter is faulty -

Today I fitted another coil, another ISC, replaced some dodgy vacuum hoses. I further cleaned........again......the TPS plugs, all good. Although the car idles ok, I thought of replacing the ISC as the idle drops when A/C is turned on, bugger, same thing happening again ! Took car for drive......heaps better. Went to servo to treat car and daughter with some PULP. She is a student with limited funds, so always have hand in pocket to help her out !

On way to servo.....hooray, fixed problem. On way back, problem came back, but not as bad. Checked timing as best I could, but don't understand about this shorting wire procedure. Timing appears to be ok, 13' BTC.

I have run out of ideas..........anyone ? Thanx in advance.

in two weeks in this forum and you will know everything you need to know about the car

Will see what I can do to get a procedure and pictures -for your tuning question
will post up in here ...by monday pm

4 cyls dont run so well with full tank of ethanol -.- you need to clean or replace the fuel filter more often

if you time to 13 degrees that is ok for now...... till we get you sorted

Edit::good you cleaned the Maf

tuning --would you like to know how to diagnose the EFI system with an LED test light the flashes system and fault codes list ?

Hi magna buff, thanks for the reply. In relation to fuel, I do not use ethanol. Daughter uses straight 91 or I supply 95 or 98 for her. Tonight I topped her tank up with 98 so she can have a full tank for the start of the week.

Last week I removed the MAF sensor & it was fairly clean, however, I bought some MAF sensor cleaner which cleaned it even better. I cleaned all connections etc., made them all bright & shiny. Daughter rang me an hour ago & said car is running a lot better.

I would be interested in the info re; timing etc.

Thank you for your interest & other members for your advice.

start of the LED diagnostics - diagnostic plug is near the inside fuse box

http://www.aussiemagna.com/forums/showthread.php?p=1197270#poststop

Magna buff, I've done the ignition timing on a TS EFI 2.6L engine - there are two plugs hanging down from the firewall (under bonnet) on the passenger side, one is flat = power to the fuel pump for testing (goes to battery +), round one with a cap and single connector, this one goes to earth. (wire under one of the strut top nuts will do). With it connected (= advance cut) ignition timing should be 5 degrees BTDC.

Don't get the two mixed up, or connect to the wrong polarity.

thanks MadMax .8,644 ;posts .you should be a moderator :thumbsup:
"quote Madmax

there are two plugs hanging down from the firewall (under bonnet) on the passenger side, one is flat = power to the fuel pump for testing (goes to battery +), round one with a cap and single connector, this one goes to earth. (wire under one of the strut top nuts will do). With it connected (= advance cut) ignition timing should be 5 degrees BTDC.

Don't get the two mixed up, or connect to the wrong polarity.
end quote .

http://i253.photobucket.com/albums/hh59/magnabuff/timing.jpg (http://s253.photobucket.com/user/magnabuff/media/timing.jpg.html)

Magna Buff & Mad Max,
Thanks for all the relevant info that was sent to me. I found the timing check connector yesterday as per the photo. Question is, how do I use it ? Do I remove the top off in order to connect a wire to it which in turn I earth the other end of wire to strut bolts & then I hook up timing light as per normal ? I'm a bit slow on the uptake in relation to this plug. How do I use it ?

remove the top off in order to connect a wire to it which in turn I earth the other end of wire to strut bolts & then I hook up timing light as per normal

Just like that! lol

Thanks guys, now i know what i am doing. You guys are great 😊

Max Max knows heaps .

any other problems that happen with the car -
make a new topic.