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View Full Version : We may be an endangered species but not extinct yet!



coldamus
12-10-2013, 06:40 PM
Nice to see some new members keeping the 1st gen forum alive and existing members persisting. I'm persisting too as I've just bought another TP.

As Rumpfy, Vee and others will recall, I was having continuing problems with rough running of my TP carby sedan. It gradually became worse and a transmission problem (defective lock-up clutch) also became obvious. The car needs new tyres and a complete exhaust system as well. It is not economic to fix, so I've been looking out for a replacement.

My budget is very limited, but eventually I found what I was looking for - a TP at a realistic price with a few months registration, low kms and reasonable prospects of passing the next roadworthy check. Oh, and efi (praise the lord!).

It is a 1990 TP Executive sedan. I'd have preferred a wagon but beggars can't be choosers. The location was about two and a half hours from here, so I drove down in the carby sedan to check it out. The interior was good but the engine bay grotty and the exterior worse than expected. It must never have been polished in its life as the paint is extremely weathered and dull. The colour is Tuscan Beige (an insipid shade of cream) but at least that has no clear coat, hence no peeling. It had been parked in the open under trees, so there were bird droppings all over it.

There are a couple of rust spots - a small one on the roof, a couple under the door protection mouldings and the usual spots in the lower doors - nothing too serious. The panels are straight and the only dent on the whole car was a cricket ball sized indent in the lower left side of the front bumper. There were 61,460 kms on the clock which I was assured is genuine. The same family has owned it since new.

It drove better than expected, so I made an offer, bought it for $800 and drove it back home. No problems on the 200 km trip. The engine is smooth, the air cond actually works, no signs of overheating and the transmission seems fine. The lock-up clutch works properly so rpm at 100 kph is around 2300 rpm as compared to 2600 to 2800 for my carby sedan.

I returned by train and bus the next day to get the carby sedan and drive that back home too.

I've put in plenty of work over the past week, cleaning it up, doing oil and filter changes and fixing little things. In another week or two, it should look fairly respectable.

I swapped the towbar from the other sedan as well as the rear seat cushion and squab. Both sedans have the same interior colours, which is convenient. The front seats are like new, so nothing required there. The centre console was badly cracked, so I took it out and repaired it with fibreglass and aluminium reinforcement. I removed the front bumper and popped out the dent completely by applying a heat gun and standing on the indentation from the back side.

Today I started on the paintwork. Autobarn mixed a spray can of the correct colour for $30, so I can use that for touch ups once I've patched the rust. Today I masked off and resprayed the gloss black window pillars that had faded to grey. There are some minor things to fix but no roadworthiness issues so hopefully it should give a few years more service.

magnaman89
12-10-2013, 07:22 PM
i have done 1513km on 105 lts at 6.93 lt per 100km in a gen1 ill like to see a gen3 do that
pluss i have seen nice gen1s here in coffs harboure

veeone
13-10-2013, 09:50 AM
6.93 lt per 100km
How fast were you going and is it EFI manual? Thats 40mpg in the old scale!! Impressive
Just ordered a new Bosch Oxygen sensor for my TP EFI from USA $22 including postage. Lots cheaper there than here in Oz.
Hope to get better from mine in the future when i convert to manual from Auto. Vee

veeone
13-10-2013, 09:53 AM
(defective lock-up clutch)
Don't recall you mentioning that.
Have you checked the water temperature sensor on the inlet manifold there are two pins in it and when the lockup used to play up or to stop it working you turned the connection round so only the pin for the temp gauge is connected.
Auto trans techie specialist showed me how to do that years ago when they had problems with the early autos. Vee

coldamus
13-10-2013, 12:35 PM
(Defective lock-up clutch)

Don't recall you mentioning that.
Have you checked the water temperature sensor on the inlet manifold there are two pins in it and when the lockup used to play up or to stop it working you turned the connection round so only the pin for the temp gauge is connected.
Auto trans techie specialist showed me how to do that years ago when they had problems with the early autos. Vee

Remember I mentioned rythmic tacho fluctuations when cruising and also a strange vibration going uphill under load. The tacho fluctuations were due to the lockup clutch continually engaging and disengaging and the vibration was due to it slipping under load. It was getting worse and was obviously on the way out, so I decided to disable it to prevent further damage. At least in my carby TP, the water temp sensor only has one pin and does not affect the transmission. The transmission has its own oil temp sensor.

There are 3 sets of wires from the transmission, each with connectors that slot onto a bracket mounted between the brake reservoir and the strut tower. One is 4-pin for the shift solenoids, one is 4-pin for the two pulse generators (A and B) and the only 2-pin one is for the trans oil temp sensor. The wires are sheathed but you can pull back the sheath at the ends to see their colours.

On the transmission side of the connector, both wires from the oil temp sensor are red. On the other side, the wires are green with yellow stripe and brown with black stripe and they go to pins 8 and 4 of the TCU respectively.

The temp sensor is a thermistor with resistance of 2.5k to 2.7k ohms at 20 degrees C, 630 to 690 ohms at 60 degrees C and 210 to 270ohms at 100 degreees C. The TCU interprets the resistance value and uses the temperature information for various purposes. One purpose is to disallow power mode below 20 degrees C and another is to disable the lock-up clutch below 50 degrees C.

I fitted a double pole changeover switch in a small box and wired it into the circuit so that with the switch in one position, the temp sensor is connected to the tcu as designed. In the other position, a fixed resistor is substituted for it. In order to make power mode available but not allow the lockup clutch to operate, I wanted to simulate a temperature above 20 degrees C but below 50 degrees C. I figured 1.5k ohms would be about right but didn't have that value resistor at hand, so I used two 2.7k resistors in parallel, giving a value of 1.35k ohms. It works exactly as expected. The vibration under load disappeared and the tacho fluctuations too.

I'm not suggesting anyone else do this unless your lock-up clutch is almost stuffed and you can't afford to have it fixed properly. Disabling it increases cruising rpm and consequenly fuel consumption. In my case, it was already slipping badly and virtually useless, so fuel consumption did not get any worse and it bought me some time while I looked for a replacement car.

In the pic below, the connector from the temp sensor is the rear one. Don't rely on that though as the 3 connectors could have been moved around on the bracket. They slide onto 3 metal blades on the mounting bracket. The temp sensor connector is the only two-pin one. The way I have done it is overkill really. You could just cut the two wires between the connector and the tcu and solder a resistor across them. Even easier, just leave the connector disconnected but then you won't have access to power mode.

http://users.tpg.com.au/acheson1/images/trans_wires.jpg

magnaman89
13-10-2013, 02:35 PM
How fast were you going and is it EFI manual? Thats 40mpg in the old scale!! Impressive
Just ordered a new Bosch Oxygen sensor for my TP EFI from USA $22 including postage. Lots cheaper there than here in Oz.
Hope to get better from mine in the future when i convert to manual from Auto. Vee
the funny thing about it was i changed the alternator before i left and forgot to connect up the o2 sensor.
how fast was i going lol

Tpwagon
13-10-2013, 03:20 PM
My old first gen is getting a bit of loving as well. Fitting news front struts today,need new bearings and bump stops so hopefully buy them tomorrow and finish it off. It's funny others are having lock up clutch probs,mine is pretty bad as well. I have a TR engine built up to go in her soon so when I'm doing the swap I'll get the trans sorted out. My mounts are buggered so I scrounged up a good pair of left and right mounts and new front and rear. I did the sikaflex fix to the used mounts to give them a better chance of survival. By the way,if anyone needs a fuel sender for a wagon let me know,I was sent an analogue sender instead of the digital one....I got my sender rewound and is working fine so the analogue sender is sitting here waiting for a new home.Long live the first gens!! By the way,there's a few cheap tp's on gumtree if anyone needs to expand their fleet:hmm:

magnaman89
13-10-2013, 04:33 PM
there's a few cheap tp's on gumtree if anyone needs to expand their fleet:hmm:

i have 10 allready i think im expanded anoth lolo

Tpwagon
13-10-2013, 04:59 PM
i have 10 allready i think im expanded anoth lolo

10! Man,you really are keen,you must have the market cornered. Old cars are a bit like stray dogs ,some one needs to give them a good home!

magnaman89
13-10-2013, 08:46 PM
coldamus your right
if you drive or own a gen1 you don't belong on amc mm13 has proven that
before im baned

veeone
14-10-2013, 07:54 AM
how fast was i going
Well i have had several Magna 1st gens TN and TP series and never even got close to that sort of fuel consumption on the highway at 100km/h with airconditioning on. Best 9 litres per 100 so thats why i asked about speed in case you were doing 80km/h all day like a friend of mine with a commodore does and raves about good fuel economy...........in the real world not so good when everyone does 100km/h. Like Europe they have
56mph they use for fuel consumption tests on all vehicles. Motorways are 70mph in UK.
So was your car Auto or manual? Vee

veeone
14-10-2013, 07:56 AM
Ok remember the tacho fluctuations must have missed the post on your fix. Cheers good to know!!
The twin pin sensor is on carby models for the lockup clutch. Vee