Underpowered in 4th gear!!! 300tdi auto

Begining:

I have a 1974 Series III with a 300tdi engine, i recently noticed that on cold mornings it was a bit well Chuggy, i took it to the mechanics and asked them to clean the injectors, this fixed the early morning Chuggyness,

Problem since the injectores have been clean:-

1st, 2nd, 3rd gear flat stick no dramas, when the Auto box changes to 4th gear it dont want to go anywhere, just drops back to 3rd to try and power on. Repeats itself over and over. this primarily happens on the flat and uphill.

Diognosis:-
Injectores-Fine
Injector pump-Fine
Head-Fine
Compression-Fine
Turbo- Fine currently running at 14psi
Gearbox-Fine
Drivertrain-Fine
Electronics-Fine

everything my mechanic, the injector and turbo specialists have tried and tested has come out fine.

Any Ideas??

I personally Think there is a lack of fuel getting into the block when in 4th gear, considering the injectors were the last things played with it has to be something to do with the fuel system but as far as they are concerned everything is working fine.

My theory is this, in 4th you are in your lowest gear thus creating more stress on the engine up hill at low rpm, if there is not enough fuel to bring the rpm up then the turbo cant spool and thus give more power. beacause it is an Auto box it automatically selects the gears to suit the conditions and changes back down to third.

I have mentioned to my mechanic i think this is what they have done wrong but well you know how they are sometimes they think peeps who dont work as a mechanic dont know anything, now i may be wrong but thats the whole point of this forum.

Has anyone had a similar problem or is anyone a landy specialist who knows this engine well who could help.

Although i have tken it to a landy specialist i am in australia and well, they aint poms and dont really know landys, they like there landcruisers and Nissan patrols lol.

Thank you for any assistance you can give me.

Hello, welcome to the forum

It sounds like a very frustrating problem, and it's sods law that these things always tend to crop up every time you do something to rectify an existing problem. Bearing in mind the mechanic has tinkered with your injectors, there are a few things I need to ask. Firstly, how has said mechanic supposedly cleaned the injectors? A lot of lazy slack arse mechanics will just throw a couple of bottles of 'injector cleaner' into your fuel tank, or at best fill your fuel filter solely with injector cleaner and then allow it to work its way through the lines and into the injectors. If they have done the job properly, and removed the injectors from the head then they may have skimped on a few critical components when they were re-fitting the injectors. It is important that you always fit NEW copper injector sealing washers before they are put back into their slots in the head. When the spill rail was reattached (the smaller pipes that enter the side of the injectors), they should have also fitted two new copper sealing washers per injector, one on either side of the pipe union. I'd thoroughly check that they have done this. It may involve you having to remove the injectors yourself in order to fit new sealing washers. Also check that the injector pipe nuts are tight (but don't over tighten them) at both the injector and the injection pump ends. The mechanic may have slackened one or more of them in order to purge the fuel system of any air and forgotten to re-tighten it. Also ensure that the boost diaphragm vacuum pipe is fitted correctly. This is the length of pipe that runs from the turbo to the top of the injection pump. If it has been knocked or removed, the fuel will not give the engine an extra boost of fuel when the turbo is boosting.

Other than that, it could be that your fuel filter is clogged, or the air filter needs replacing. I'd check both of those, and replace them as a matter of routine maintenance anyway, it'll only cost you a couple of quid. Never fit Britpart (known around here as ****part) filters, or any other components to your landy. They're not worth the money that you'll spend on them. I replace my fuel filter twice a year if not more because it clogs up with crap extremely quickly.

-Pos

The injectors were removed and cleaned in a machine, im not sure if they have replace the copper washers or not but i will have a look. i have got it back for the weekend and i will replace the fuel filter, air filter and check those components that may be loose, still it seams very strange that in all other gears the power is there.

Thank you for your help so far, i will keep you updated.

if they didnt replace the copper washers then they arent proper mechanics IMO

has the GB fluid ever been changed ?

have you checked the insides of the CAF hose for collapse/delaminated - this is common but ONLY when the engine is working hard
IC (if you have one) is that clean

rather than just thinking if's a fuel issue ponder that it might be an air issue, no point having fuel if the engine doesn't have any air

Sounds Dumb but what is the CAF hose? (cool Air flow hose)?
all oils and flids were changed less than 5000k ago,
the Intercooler seems clean and free from crap.
they have replaced the coppers as far as i can see.
As of caution i will change the fuel and air filter tomorrow and see if that helps, im not sure it will though as it was running perfectly fine before i they cleaned the injectors.
this brings me onto something i did find.
Injector Fuel run off, aint there supposed to be fuel that lubricate's with working parts of the injectors? after the fuel runs back to the pump and then back to the fuel tank, i have a filter that is on the line back to the fuel tank and i swear before i took it in there was fuel in the filter but its bone dry now, so naturally one would belive that there is no fuel being passed back through the system to lubricate it. am i right in saying there is a spring in the injectors that needs this run of fuel for lubrication? could this be what the problem is?

davidcbond said:

Injector Fuel run off, aint there supposed to be fuel that lubricate's with working parts of the injectors? after the fuel runs back to the pump and then back to the fuel tank, i have a filter that is on the line back to the fuel tank and i swear before i took it in there was fuel in the filter but its bone dry now, so naturally one would belive that there is no fuel being passed back through the system to lubricate it. am i right in saying there is a spring in the injectors that needs this run of fuel for lubrication? could this be what the problem is?

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CAF is cold air feed

think your on about the injector leak offs, which is a series fed line from the injectors - where is this filter you mention ?

is that something you've added ?

okay it goes like this, Injector leak offs, back to Injector pump, through pipes to small see through filter and back to fuel tank. This vehicle is not standard it has had some work done to it but nothing major, the previous owner was a landy specialist, i wish i could get hold of him and ask him but unfortunatly he is going through some troubles in his life and i dont think he would care much for me right now so i dont want to bother him. this extra fuel filter is just a standard in line see through fuel filter nothing special.
surely there must be fuel that bleeds back through?

davidcbond said:

okay it goes like this, Injector leak offs, back to Injector pump, through pipes to small see through filter and back to fuel tank. This vehicle is not standard it has had some work done to it but nothing major, the previous owner was a landy specialist, i wish i could get hold of him and ask him but unfortunatly he is going through some troubles in his life and i dont think he would care much for me right now so i dont want to bother him. this extra fuel filter is just a standard in line see through fuel filter nothing special.
surely there must be fuel that bleeds back through?

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Seems to me it was only a bit chuggy in the mornings until some clown fooked about with your injectors.

Stick a set of new injectors in and start again.

over here injectors cost 200 each minimum

get them cleaned and serviced

they have been cleaned and serviced

davidcbond said:

over here injectors cost 200 each minimum

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Your gona go around in circles until you are confident it aint them tho. I have tested injectors many times and they look ok but ended up sticking another set in and wondered why I fooked about in the first place.

Only other option is overhaul yur own ones as the other chappie says.

davidcbond said:

they have been cleaned and serviced

Click to expand...

And its worse now!!

lift pump shagged possibly-have you checked flow

yes it is, read what i have put on the top of the first page and read the story might shed some more light for you.

yes sorry the fuel system has been checked by a specialist and everything is a okay

there is no mention of "lift pump" from what I can see or firefox search can see.

You mention injection pump, lift pump is not the same, a worn lift pump would give poor running at high rpm/load-further to this if engine is running it is wrong to assume it's okay. split diaphragm or worn valves in it would cause high speed issues

in every gear other than 4th the motor runs with no probs at all, they have checked the flow also and it also checks out this is very frustrating.

So as a test, stop it from dropping into top by selecting the highest gear apart from D.
Find a long steep hill drive it once sedately up, once bury throttle-if on both occasions you have no fault-I'd be looking at gearbox fault.

300 tdi I have not had anything to do with, unless the auto box is getting engine feed back from MAF(load) and an rpm signal-it doesn't make sense to have fault in one gear on engine

Auto box without electrics - mechanical governor play up and also has the box filter/screen been cleaned-what box are you using and early 300tdi?

Symptoms and Repair of Transmission Seal Problems

Todd Pfortmiller reported in with the problems he was having with his transmission, which turned out to be due to worn seals. "Upon startup, the vehicle drives fine for a little while. Then as the transmission fluid warms up, after a complete stop Drive will not drive. It feels like a little lunge, but that disappears immediately. A quick manual down shift into 1 to engage the mechanical linkage (as I understand it), gets the beast going again. Up shifting 'manually' works fine, and even a severe kick down at highway speeds to climb an 8% grade is not a problem."

Todd's Land Rover tech suspected the three governor seal rings (RTC4660). This turned out to the case -- and the repair procedure is described on the separate Transmission Seal Replacement page.

Click to expand...

http://www.rangerovers.net/repairdetails/drivetrain/transrepair.html#governor

see they thought it was the gearbox but they have checked it and they say its all good. plus how can cleaning the injectors cause the gearbox to go up the ****ter? before they cleaned them everything was fan bloody tastic just a little smokey when i put my foot down thats why i wanted them cleaned, i really think that they have done something wrong with the injectors but they cant find out what. Everyone they have talked to has said what it is doing is impossible and they have never heard of it before, and all these guys are supposedely specialists,

i really honestly think that the injectors are not getting any fuel lubricating the springs inside the injectors