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General Information => Troubleshooting => Topic started by: 2strokesmoke on December 01, 2013, 08:00:42 pm
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Hi guys,
While I have owned many 1.6D's - this is my first Turbo diesel
I have a question about boost PSI at highway speed (65 MPH)
I'm running 9 PSI @ 65 MPH on Level ground,no wind,just myself in the car(no cargo)
The car is an 88 Fox GL wagon,which I purchased from someone on the Vortex over a year ago.
It has a 1.6TD conversion-engine & trans from an 85 Quantum (T3 turbo,NO intercooler,2" ID exhaust
with cherry bomb muffler)
I estimate the car weight to be around 2000 lbs to 2200 lbs
Door sticker says GVWR 3050 lbs
Does 9 PSI at a steady speed of 65 MPH on level ground seem right ?
Pressure reading is taken from a "T" fitting-which is in the hose going from intake elbow to IP
How much PSI are you guys running?
I've also noticed- at idle I read -2 or -3 (vacuum) with a clean air filter
I have double checked my gauge(snapon mechanical gauge) which is accurate and does rest at "0" with engine off
Thanks for your input
Mike
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Depending on the gearing that should be about right. With wastegate turbos you can't really change the cruising boost level unless you set max boost lower.
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If you had a turbo with a later style waste gate on it, you could apply vacuum to one side to open the waste gate fully while cruising.
Not that it really matters anyway.
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So many variables...
My car runs 7-12 on flat ground at 70 by changing only how hard rain is falling.
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if thats the quantium turbo... seems high to me..
quantiums i think were bigger then the mk1/mk2 of the era.. and mine runs abt 3psi at 65 on level ground in my b3... vs the tdi pea shooter of 12-15psi pn my kubvan..
but what engine rpm you abouit? tranny choice may be your issue..
fyi vanagons had a quantium style turbo but was smaller... so again turbo info helps.. over the pond..
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Hi Guys,
Thanks for your input !
I gather my 9PSI is about right then.
I don't have a Tach,so I don't know what RPM is.
I'm guessing it low.
Prior owner installed a trans with a tall 5th gear
I don't remember what car it came out of, just that it was from an audi.
Is it normal to have -2 to -3 (vacuum) at idle and just above idle ? (new air filter)
Thanks, Mike
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Do you have an EGT gauge?
What does that read?
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Vac depends a little on the gauge and what your elevation is. At 10,000 ft. of elevation with a cheapo gauge, sure. Assuming your gauge is working correctly and your location (Long Island, New York - sea level) is accurate, then no, you should not see any vacuum.
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Thankyou for the replies.
I don't have an EGT
Yes gauge is accurate
You are correct- I'm at sea level
What would cause vacuum at idle & just above idle ?
I have a new airfilter.
Intake manifold is clean,intake boot or hose is good, no leaks
Can Cam timing effect this ?
Thanks,Mike
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oil soaked filter?
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Air filter is clean-no oil
But thankyou
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Intake restriction.
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The Intake manifold,elbow,turbo,intake boot(from turbo to airfilter box),air filter,ect..are all clean and no obstructions anywhere.
I've also noticed that the Vac/Boost gauge ocassionaly flutters at idle (maybe 25% of the time)leading me to believe there is a bad intake valve (With Properly adjusted valves-mechanical head)
The reason I asked if incorrect cam timing will cause vacuum at idle & just above Idle(sometimes up tp 1500+ RPM with no load)
Is this:
I have suspected that my crankshaft TDC mark is incorrect (odd as it sounds)
I bought this car with engine & trans already installed- I finished the 1.6TD conversion
Prior owner stated that flywheel and clutch were from the same 85 Quantum 1.6TD
I timed the engine using correct IP lock pin & Cam Lock Plate I have used many times before & set IP to 1.05.
Tripple checked everything,like I always do.
Engine started instantly,was smokey,Had NO power at all and barely rattled at all (very quiet)
So I reinstalled dial indicator,double checked IP timing & cam timing- All the same @ 1.05
When I registered the car a few months later and took it for a drive- I could barely reach 50 MPH and tons of fuel smoke.
Finally I threw out the specs and advanced the IP timing by ear. ( I had to advance it a LOT to make it sound right.)
The engine still starts instantly and runs good,but is Smokey (fuel smoke) and really doesn't make any power until boost.
I also have the -2 to -3 Vacuum at idle and vacuum will reach -5 to -6 at around 1500 RPM (No load)
I've never seen this before.
I've been driving the car this way,for about a year and have turned the fuel down as low as I can & still have fuel smoke (any lower and I won't reach 55 MPH)
Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike
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Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike
There was a post in a thread about this last week, can't find it though.
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Is there any way of determining TDC without removing the head or oil Pan ?
Does this make sense to anyone ?
Thanks,Mike
http://www.vwdiesel.net/forum/index.php?topic=34145.0
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If you look into the turbo at 1500 RPM, are the blades turning? They should be. Is the vacuum gone with the intake tube removed?
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Thanks for the replies !
I never thought of looking at turbo,while running.
I'll try that for sure.
Thankyou for the link to finding TDC. I didn't know you could send probe thru the precup. Thats awsome !
Thanks,Mike
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If you are worried about the flywheel timing mark;
Sometimes the clutch can be put on wrong, even though there are alignment pins.
On the other end of the crank, there is a bump on the timing belt sprocket that should be the about 7:30 at TDC,
Kinda sounds like you are 180 degrees out on timing.
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I don't think you can make 9PSI or 65 MPH while 180 out. Mine would barely turn around in the driveway.
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I don't think you can make 9PSI or 65 MPH while 180 out. Mine would barely turn around in the driveway.
You totally can if you tune the pump... I assembled a pump 90° out a decade ago and got it tuned up so it had very similar power and as much or more boost. The only clues were higher EGTs, more diesel clatter, a small amount more smoke and a little bit harder starting.
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I don't think you can make 9PSI or 65 MPH while 180 out. Mine would barely turn around in the driveway.
Your experience may vary.
Fuel still burning when it hits the exhaust helps spin the turbo.
I would expect alot of smoke though.
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The one that I messed up on really didn't smoke much. Just slightly more than normal but it did so even at low fuel settings and so I knew it wasn't quite right.
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I appreciate all your help.
I need to wait until a warm day,to check TDC against flywheel mark and also check IP marks.
Currently I have the engine out of my K2500 and disassembled in the garage (spun rod bearing on 5.7L)
So no garage space available right now.
Sold my Caddy 2 months ago
So The Fox is my only vehicle at the moment,so I can't lay it up for long.
I'll keep you all posted,
Thanks again,Mike
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Update-
Finally had a warm day,to work on my VW
Used dial indicator thru #1 injector hole,to check TDC mark
TDC mark IS ACCURATE
Checked cam timing,which is perfect
while I was there, I checked cyl head torque and valve clearances - all perfect.
I checked and adjusted IP to 1.08 . (was more advanced than that)
I'm thinking it may need an advanced setting to sound right,due to injector pop pressure ?
All 4 injectors were rebuild & pop tested less than 4K miles ago -by a member on the vortex
I would like to check IP internal pressure (started a new topic for this)
Will low IP internal pressure cause fuel smoke & low power ?
I also checked turbo at idle (as recommended) and it is definately spinning.
With IP set at 1.08 engine sounds right and I MUST pull out the cold start cable,or it won't fire without excessive cranking (cold engine)
With Cold start cable pulled out- It starts instantly (1st or 2nd comp stroke) and runs good below freezing temps
Thanks,Mike
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Forgot to mention-
I checked IP for 180 out (pop out paper wad test)
It is difficult to turn over this engine by hand,because crank pulley is only 1/2" from core support (longitudinal engine)
Cant get a ratchet or even a wrench in there,due to pulley mounting studs and tight clearance.
So I can only turn a little at a time,using a prybar between studs.
I couldn't get the paper plug to "pop out" ,even after 8 revolutions with prybar (had key on-power to solenoid)
Finally I put a clean dry paper towel under the IP #1 delivery valve.
No fuel after 1 revolution
a little bit of fuel trickled out on 2nd revolution
I think I maybe turning engine to slow,to "pop the plug"
IP sprocket woodruff key is at 10 o'clock
So I'm thinking pump is set right (NOT 180 out) (I was hoping it was that simple)
Thanks,Mike
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I'm not sure what the paper test is.
If you want to see fuel from a delivery vale the accelerator lever should be set to max.
Not much fuel per stroke at idle.
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Turning the engine over that slowly will result in the pump delivering more fuel than max running fuel.
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Not much fuel per stroke at idle.
While this is true, idle is the least fuel injected.. ust because the pedal and throttle are at idle positions.. does not mean the pump is internally at idle.
Turning the engine over that slowly will result in the pump delivering more fuel than max running fuel.
Yeah, starting is MAX pump fuel is it not?
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I had the throttle in the idle position,while doing the "paper wad test"
I started a new topic,about checking IP pressure:
http://www.vwdiesel.net/forum/index.php?topic=34265.0
Ends up I think I found the problem.
While holding RPM @ 2000 for OVER 30 seconds,air bubbles start to appear in the clear fuel line
feeding IP. No air bubbles at idle or below 2K RPM
Bubbles started after 30 Seconds A 2K RPM and the longer I held that RPM the worse it got.
I checked for bubbles many times before-but never held the RPM for that long.
Been driving the car for 2 days now-no smoke.
I'm a happy camper !
Here is a copy of what I posted in the above thread:
Hey guys,
Well I checked my IP pressure @ 1000 RPM which was at 28PSI
Before adjusting, I checked at 2000RPM as well (also very low)
While holding RPM @ 2000 for over 30 seconds- I think my true problem showed
Air Bubbles in the clear line to IP !
No bubbles at idle,but after 30 seconds at 2K, the bubbles started flowing-and got worse the longer I held the RPM
This really pisses me off !
A year ago, I installed a NEW fuel tank,new one piece steel feed line and new one piece return line-
From tank to firewall- no fittings or splices-all one piece- to avoid this from happening.
I had also installed a new OEM lift pump,in the tank.
It is a free flowing pump (meaning- with pump OFF- fuel flows freely thru it)
At the time,I had read many posts about using a lift pump
Some people swore it was a good idea,some people swore it was a bad idea
I figured-sence it was a free flowing pump, I could easily disable it by removing the pump relay (this is in a Fox 1.6TD conversion)
So- I have been running with pump off
Guess what- I put the pump relay back in
with pump ON,no more air bubble at all (and no leaks) and IP pressure increased to 35PSI
So I adjusted pump pressure to 43 PSI @ 1000RPM with pump ON
Now have very little fuel smoke at idle,don't see any smoke behind me while driving,turbo seems to spool a little sooner,engine sounds better-power is still about the same though (may be partly due to gearing (2500RPM @ 65MPH)
I will run it this way for a while,to make sure smoke is gone,than maybe I can turn fuel up a bit,to help power
Hopefully those darn air bubbles are gone for good.
I had a Full tank of fuel,when I checked IP pressure
So I wouldn't think I would be sucking air,from inside the tank-
I checked hose connections at tank,at fuel filter,ect- all good,all tight,all dry.
I'm begining to wonder- maybe when I checked the lift pump(before install)in was in just the right position-so it would free flow easily
then once I installed it and tested it, the pump internals were now in a different position,so it wouldn't free flow as easily ?(causing a restriction)
The only thing I can think of.
I guess time will tell
Thanks to all for your help & suggestions !
Mike
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So is it dependent on the inline fuel pump to run properly? If so, what happens the first time your fuel pump (electric) dies and you are stranded?? Scary thought.
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It runs and drives,with elect fuel pump off,but smokey.
The car smoked sence I bought it(a year ago)- but not as bad
The smoke was slowly getting worse -over time.
So I'm not to concearned about when the elect pump dies-as the car is drivable either way.
This is what I'm thinking:
If the elect pump last 1 year then dies- I'll drop the fuel tank & try deleting the elect pump.
If the elect pump last 10 years- then I'll probably put a new elect pump back in.
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Oh ok lol.
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Do you have a clear fuel line going from the I-pump to the tank? Any air?
Air in the fuel usually means a fuel line restriction is causing a vacuum that is expanding disolved air in the fuel.
Not understanding why it would flow more fuel while turning by hand without the accel lever pulled than it would with?
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Starting is pretty much a max fuel scenario as the pump tries to compensate for 100 RPM idle regardless of throttle position.
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oh, because the flyweights aren't pushing it back.