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Engine Specific Info and Questions => IDI Engine => Topic started by: shox75 on May 04, 2005, 12:47:37 pm
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some concerns.
The engine was rebuilt about 15,000 kms ago. So i thought I'd re-adjust timing.
First off i found that camshaft was a bit off, was further clockwise compared to the crankshaft. So i adjusted it flat with cylinder head.
At this point I should have tested the car to see a differance, but i didnt.
Next I Adjusted the pump to 1.03/4mm, my indicator was not that great.
I am not 100% sure where it was before, but i believe it was more past 1.05 like 1.07/9mm.
Anyway, car was running awesome before, engine very smooth good power, but had bad economy, only getting about 650kms per tank fill (mostly city).
Thats why i wanted to adjust.
Now the engine seems to run well when hot, but it is almost, but not as smooth, and when cold it knocks harder then before. Power is there, but it seems like before it was a little more sensitive (quicker revving).
My enrichment screw still has the tamper nut on it and is a bit backed off from there because of my economy issues, id get 600kms on a tank if it was in all the way, and more smoke too.
I just want this car with stock shape to be set for best power and economy. Any suggestions? Im planning on playing around with it some more today, need to adjust idle, it is higher now!
thanks in advance. Sabi
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Question:
Is it an Eco-Diesel, or the MF? I have never encountered the Eco before 'cause it doesn't exist in Canada, but have just recently adjusted my Canadian spec MF Jetta's pump to work optimally with stock boost levels. If you are running an MF, or know that your fuel pump is the same as the MF, read on.
1) Ditch the tamper collar on your load screw. It serves no purpose if you are tuning the pump yourself anyways.
2) After reading my recently acquired Bentley manual, I found that the idle on newer (90 - 92?) 1.6 TD's is adjusted via a slotted rod and spring assembly on the firewall side of the pump ALONG with and in conjuction with the idle stop screw associated with the throttle arm. The idle stop screw is used to adjust initial residual fuel level. After adjusting this counter-clockwise to the point where your idle decreases no further, you can then fine tune your idle (if needed) with the slotted rod and spring. Having the initial fuel level just right makes for snappy throttle response. Mine was out a fair bit until I got it right, and WHAT a difference it makes!
3) If it's economy and power you're after, I'd suggest that you increase your fuel load slightly anyways. Stock fueling is too low, and a slight increase will markedly improve driveability. Adjust the fuel load screw and test your adjustments so that there is just a slight amount of smoke prior to full boost. On boost, there will be no smoke. Your car will drive more like it should. Adjust idle after each fuel load increase, then test results
If you car is still not performing like it should, you may need to think about some maintenance points like: new fuel filter, rebuilt injectors, new air filter, etc. Maybe you've already done all those service points, I don't know. Thought them worth the mention. Either way, adjusting your pump to work efficently with stock boost levels is a must in my eyes after having done so myself. Very simple, very noticeable improvement.
Good luck!
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Here are the specs and what I did so far.
-Not ECO.
-Engine fully rebuilt.
-Compression 460psi across 4 cylinders. Should it be higher at 15,000kms???
-Crank and cam, timed to Bentley spec.
-Pump timed between 1.02-1.04mm. Should it be coser to .95?
-Set idle to Bentley spec. Residual volume is set at old idle adjust, but not sure wat its for? There was no tamper cap here!
-The tamper cap i was previously talking about is on that other adjustment screw that the Bentley doesnt talk about, the one with the 13mm lock nut. I just turned this in as far as the tamper allowed it. (kinda scared to take this off) Is this the fuel load adjustment?
-Machined flywheel and new clutch.
-Front oil charged mount. Is the stiffer rubber one better?
-New fuel filter, oil filter, semi-synthetic 15w-40 oil as of 2 days ago.
-Picked up new fuel lines to fix some minor return line leaks at the injectors!
-Cleaned my K&N box filter with new oil, is K&N a bad idea???
So today i drove it all day. First start after adjustments last night was a scary one. The engine ticked as i said like i've never heard it, hoping i can get to school in the morning. This morning it started up with barely a crank and idle smooth even cold, and on the way home it was as nice as it used to be.
Do these engines not like adjustments or something? It seems like mine needed time to get used to them before it started to operate properly. ???
Anyway im happy, thanks 92A2VWJTD. I hope i got the residual setting correct.
Put the tank full and lets see how my economy goes.
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Don't retard the timing any more. More advanced timing is better for fuel economy.
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Don't retard the timing any more. More advanced timing is better for fuel economy.
So by advancing you mean closer to 1.05mm right??
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Don't retard the timing any more. More advanced timing is better for fuel economy.
So by advancing you mean closer to 1.05mm right??
set it as close to the maximum allowable timing as you can get it. You will get better fuel economy and better performance. Your car is a 1990 1.6 right? How many litres of fuel do you use in 650km? My jetta does 680km on 32 litres so if yours is doing 650 on 32 litres, it is pretty close to what that car is capable of. I have redline in my transmission and this has gotten me an additional 2-3mpg per tank, so that could be why my mileage is slightly higher than yours.
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-The tamper cap i was previously talking about is on that other adjustment screw that the Bentley doesnt talk about, the one with the 13mm lock nut. I just turned this in as far as the tamper allowed it. (kinda scared to take this off) Is this the fuel load adjustment?
Roger, that's the load screw. So long as the 13mm lock nut is secure, there's nothing to fear. Like I said before, the stock boost levels can use a wee bit more fuel under load, maybe about a half or full turn clockwise.
Glad to hear your unit has decided to be good though :wink:
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Chrissev: Where were you able to find the redline? I'm not having any luck finding it in Sudbury.
Thanks, Steve
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Don't retard the timing any more. More advanced timing is better for fuel economy.
So by advancing you mean closer to 1.05mm right??
set it as close to the maximum allowable timing as you can get it. You will get better fuel economy and better performance. Your car is a 1990 1.6 right? How many litres of fuel do you use in 650km? My jetta does 680km on 32 litres so if yours is doing 650 on 32 litres, it is pretty close to what that car is capable of. I have redline in my transmission and this has gotten me an additional 2-3mpg per tank, so that could be why my mileage is slightly higher than yours.
It is the original one with the car. I usually fill it with about 42L, so i think it may be 45-50 because i never run it all the way down!
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Chrissev: Where were you able to find the redline? I'm not having any luck finding it in Sudbury.
Thanks, Steve
I got mine here: Johnston Research and Performance
Mississauga, Canada, 905-564-8805
They have a bunch of cool stuff there for performance mods. The Redline cost me $50 for three bottles. Worth every cent in improvement in shifting/less gear grinding, mileage, and power.
Here are the other dealers in Canada: http://www.redlineoil.com/dealers_international.asp?countryID=33&submit.x=31&submit.y=10
Chris
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Don't retard the timing any more. More advanced timing is better for fuel economy.
So by advancing you mean closer to 1.05mm right??
set it as close to the maximum allowable timing as you can get it. You will get better fuel economy and better performance. Your car is a 1990 1.6 right? How many litres of fuel do you use in 650km? My jetta does 680km on 32 litres so if yours is doing 650 on 32 litres, it is pretty close to what that car is capable of. I have redline in my transmission and this has gotten me an additional 2-3mpg per tank, so that could be why my mileage is slightly higher than yours.
It is the original one with the car. I usually fill it with about 42L, so i think it may be 45-50 because i never run it all the way down!
90s must have had bigger tanks. Mine is full to overflowing with 38 litres when it is on empty. 42 litres for 650km isn't that great. That's 36mpg. You might as well be driving a magicwagon. Something is definately wrong. Have you checked your tire inflation pressures? Should be at least 32psi. Perhaps a stuck thermostat? When they stick open they wreck your fuel economy because the engine runs cold and uses more fuel. Has anyone messed with your injection pump? If someone has been turning screws they could have caused the problem. Timing will get you a couple more mpg if it is set at the most advanced spot. Also there is a difference between highway and city driving. I can go as low as 45mpg with stop and go city driving, or as high as 55mpg with long distance highway driving at 120km/hr.
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Don't retard the timing any more. More advanced timing is better for fuel economy.
So by advancing you mean closer to 1.05mm right??
set it as close to the maximum allowable timing as you can get it. You will get better fuel economy and better performance. Your car is a 1990 1.6 right? How many litres of fuel do you use in 650km? My jetta does 680km on 32 litres so if yours is doing 650 on 32 litres, it is pretty close to what that car is capable of. I have redline in my transmission and this has gotten me an additional 2-3mpg per tank, so that could be why my mileage is slightly higher than yours.
It is the original one with the car. I usually fill it with about 42L, so i think it may be 45-50 because i never run it all the way down!
90s must have had bigger tanks. Mine is full to overflowing with 38 litres when it is on empty. 42 litres for 650km isn't that great. That's 36mpg. You might as well be driving a magicwagon. Something is definately wrong. Have you checked your tire inflation pressures? Should be at least 32psi. Perhaps a stuck thermostat? When they stick open they wreck your fuel economy because the engine runs cold and uses more fuel. Has anyone messed with your injection pump? If someone has been turning screws they could have caused the problem. Timing will get you a couple more mpg if it is set at the most advanced spot. Also there is a difference between highway and city driving. I can go as low as 45mpg with stop and go city driving, or as high as 55mpg with long distance highway driving at 120km/hr.
man if i had milage like that I'd drive everywhere, even to my neighbors house. The only person playing aroudn with the pump is me, but everything is set to Bentley spec.
Well I hope my last timing adjustments is going to make a difference, I can treally tell yet. Only down a 1/4 tank so far.
I set everything as i posted above, tires inflated to 42 psi all around.
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man if i had milage like that I'd drive everywhere, even to my neighbors house. The only person playing aroudn with the pump is me, but everything is set to Bentley spec.
Well I hope my last timing adjustments is going to make a difference, I can treally tell yet. Only down a 1/4 tank so far.
I set everything as i posted above, tires inflated to 42 psi all around.
42psi? what sort of tires? Might be a little bumpy ride at that pressure. I usually do mine to 32psi. Have you checked your thermostat? Checked for dragging brakes? Take all four wheels off the ground and spin them. They should spin freely. The front ones will be a bit sticky because they are connected to the drive shafts. The back ones should spin like the wheel of fortune. If they stick or are hard to turn, there's your mpg problem. The thermostat is another big mpg killer. If it is stuck open, the engine never warms up and you lose a lot of fuel just making heat which is tossed away out the radiator. That car that you have should get a minimum of 45mpg all the time. They are very fuel efficient.
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42psi? what sort of tires? Might be a little bumpy ride at that pressure. I usually do mine to 32psi.
We run my wife's '02 Golf TDI at the max pressure listed on the sidewall of the tires - 44 psi in our case. It not only helps with fuel economy, but adds to the total stiffness in what we consider a too-soft car.
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We run my wife's '02 Golf TDI at the max pressure listed on the sidewall of the tires - 44 psi in our case. It not only helps with fuel economy, but adds to the total stiffness in what we consider a too-soft car.
I'm with you on this one Stan, we're running 42# in my wife's '02 Jetta TDI. Car rides just fine, and on a recent FL trip we recorded our best milage ever @ 57 mpg for one tank through the flat Southeast! And that's hauling 3 adults, vacation luggage, and a MIG welder with compressed gas tank, all at 70 to 75 mph!
I still prefer all mechanical diesels, but I'm beginng to see the TDI light!
moT
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Just checked my mileage (92 jetta 4 door w/1.9TD) works out to 6.1l/100 km or about 46mpg imperial. Not impressed! Checked it about three months ago, presumably winter fuel then, and got about 49 mpg that time! most driving is 2 lane at 90 to 100 kph, should be better than that! As with the other guys, running the max air pressure on the sidewalls .maybe the 195/60 15's are too hard to push? Diameter of the tire appears to be pretty close to the 185/65 14's on hte wife's Jetta..........
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My needle hit 1/4 on the guage and i only did 200kms so far. From here it drops faster because the guage increments arent very acurrate.
Going to check for brake drag today, but i highly doubt that because i have rear discs and they were just done 2 months ago.
Thermostat was replaced with enigne rebuild 4 months ago, although its an aftermarket one as a recall.
Is there anyway to tell if the thermostat is stuck open from the temp. guage in the car?
Mine always warms up till its about half way, and then stays there.
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My needle hit 1/4 on the guage and i only did 200kms so far. From here it drops faster because the guage increments arent very acurrate.
Going to check for brake drag today, but i highly doubt that because i have rear discs and they were just done 2 months ago.
Thermostat was replaced with enigne rebuild 4 months ago, although its an aftermarket one as a recall.
Is there anyway to tell if the thermostat is stuck open from the temp. guage in the car?
Mine always warms up till its about half way, and then stays there.
My temp gauge does the same. Half way up and then stabilizes there. It's weird that your mileage is so low after the rebuild, because the pump is mechanical and the fuel is metered per the pump and not per the engine (ie, the pump is designed with the assumption that everything in the engine will always be the same at a certain rpm, with the exception of the boost enrich for the turbo which enriches the fuel supply depending on how much boost you are putting in). That is the only variable that is controlled by something happening outside of the pump. So mpg issues on those cars are usually caused by either something slowing down the car so that you have to put your foot down more to get it to move, or something on the pump or to do with the pump adjusted wrong so that the fuel supply is inaccurate or the delivery is at the wrong time.
If you turn the crank by hand with a ratchet and socket, does it turn freely up to TDC where you feel resistance from the compression, then when you go past TDC does it release and turn freely up to TDC again? There shouldn't be any resistance other than the resistance from the compression.