1.8T stroker high oil pressure issue

[K20017]

This engine was rebuilt around 2000 miles ago. On a completely cold start, oil pressure is around 100, sometimes 100+ (In this video, car was very slightly warm so it didn't hit 100). Once warmed up, however, everything is fine and within specification. But should my oil pressure be 80+ at 4500 rpms+? It doesn't seem right. I have no other issues with the car though, besides the fact that it doesn't like to move when it's cold (leans out, bogs down, backfires) I am using Mobil 1 5W-40.

Any thoughts as to what it could be?

[Gulfstream]

thats the numbers I usually see as well. Apart from idle where I see no less than 45psi. Im not stroked yet tho. Motor going in the car in 3 weeks, I hope...

[K20017]

Hmm, every decent mechanic that has been in my car has noted the high oil pressure. I remember reading a thread with Ed from Force Fed talking about his engine hitting 65psi max during a pull.

[babarber]

i would say 70-75psi at 7k is the max you should see

try a lighter oil 0w40 or 5w30 maybe go for

also go for a vigorous drive for about an hour or so really get your engine warm and see if the oil pressure drops any

[K20017]

Yeah, I've done the vigorous drive test but pressure is still the same. I've tried 0W-40 but not to avail. I suppose I could try 5W-30 and check the results.

[babarber]

hey just be glad your dont have low oil pressure

[K20017]

Haha yeah. But high oil pressure can cause seal problems. However, no leaks so far!

[AmIdYfReAk]

I'd be happy with that kinda oil pressure.... Just take it easy when its cold.

i ran 15W50 in the last two years of my VR6, kept it quiet and running well.... But man, the oil pressure when it was cold!!

[K20017]

Yeah, I let it warm up to 190 everytime before moving it. I guess if it ain't broke don't fix it!

[Chickenman35]

Yeah, I let it warm up to 190 everytime before moving it. I guess if it ain't broke don't fix it!

That's actually not a good way to warm an engine. Start it up, then immediately start driving it. Just keep the revs down till you start getting some temperature in the motor.

[Chickenman35]

I deleted my original post as I found new info.

100 psi when cold is quite common with many motors. Cold pressures really don't matter ( at 120psi cold I would start to worry ). What does matter is pressures when warm.

When at operating temperatures idle pressures are fine, pressures at 2,000 rpm to 4,000 rpm are fine. But high rpm pressures ( 6,000 rpm+ ) they still look like they are hitting 100+ psi. Can you confirm this? At full operating temps ( and that means water and oil ) what does the oil pressure hit at max rpm?

If it's still hitting 100 psi or more then I would suspect two things:

1: High reading gauge sender. Double check it with a good mechanical ( not electric ) oil pressure gauge.

2: If gauges check out, then I would possibly suspect a sticking bypass valve in the oil filter housing, or a spring that is slightly on the stiff side.

Main pressure relief valve is in oil filter housing. 17mm nut I believe. Pull spring and plunger and make sure that plunger is not sticking. You might have to take some " Crocus " cloth to the plunger and polish it smooth. Get rid of any nicks or burrs.

Edit: Hard to find...but I did some research and Bentley says a maximum of 7.0 bar ( 102 psi ) at full operating temps. So if you're not over 100 psi at full operating temps ( oil and water ) and max rpm...don't worry be happy

Edit 2: Did some more research and found numerous fresh builds that had around 100 to 110 psi hot at max revs and oils in the range of 5w-40..so it seems that things may be OK.

Note: Bentley manual specifies that the oil pump itself had a high pressure relief valve of 12.0 bar ( 174 psi ) !! This is on AWM and later motors with the chain driven oil pump.

[Chickenman35]

Freakin' hell VW's run high oil pressures!!

I just did some more looking through my Bentley, and AEB oil pumps at 3,000 rpm spec 5.0 to 7.0 bar!! That's 72.5 to 101.5 psi at only 3,000 rpm!! ( Engine oil temp at 80c/176f )

[jbrehm]

Yeah, I don't think that's too high with 40 weight - hot idle is fine, and the oil pump is crank driven so the pressure increases linearly (approximately anyway) as crank speed goes up. Try some 5W-30 and I bet it will drop a good bit.

I read some of your adventures with this car - I can't blame ya' for being a little paranoid! I think a lot of us f*ck around with so much stuff on our cars that we all get a little paranoid every now and then

[Andaloons]

I think a lot of us f*ck around with so much stuff on our cars that we all get a little paranoid every now and then

Words to live by!

[K20017]

That's actually not a good way to warm an engine. Start it up, then immediately start driving it. Just keep the revs down till you start getting some temperature in the motor.

Are you sure? Thought most of the wear and tear on an engine is when it is cold.

I'll do a test today with going all the way up to 7000 and check the pressure. But I'm pretty sure it is around the 100 mark.

I do get paranoid sometimes....hell, I had a dream last night my car caught fire and burned to the ground. Dream...I meant nightmare.

[babarber]

yeah i get paranoid sometimes too. when im in traffic and i hear another car making noises, i immediately think its my car

[xXGti2006Xx]

I personally don't like how that gauge is reading, seems real weird to me how it jumps up and down a lot, and how it ramps up so fast. I'm more leaning towards a bad sending unit/gauge? Im built motor/big turbo and i see like you said around 25-30psi warmed up idle, and around 80 psi max in any pull. I never was a fan of electronic sending units, i run mechanical gauges only, that doesnt lie you know

[Rac_337]

mines around 60 psi on a cold start. maxes out at 80 or so. idle sits around 30. fresh build

[Chickenman35]

Are you sure? Thought most of the wear and tear on an engine is when it is cold.

I'll do a test today with going all the way up to 7000 and check the pressure. But I'm pretty sure it is around the 100 mark.

I do get paranoid sometimes....hell, I had a dream last night my car caught fire and burned to the ground. Dream...I meant nightmare.

I had a nightmare last night too. Hooked up with my ex-wife

Regarding cold running. 100% sure of procedure. It's in the owners manual of every new car sold. And it's a proven engineering principle.

Most of wear and tear is on engine is on initial start-up. Once oil is flowing to bearings and valve-train you're golden. However, it is important to bring the engine up to normal operating temperature by immediately driving it. Main reason is to warm block and to expand pistons to their proper operating size. This reduces blow-bye into the crankcase, which contaminates the oil.

You also want to get it out of open loop ( Rich startup ) and into closed loop as soon as " reasonably " possible. Warming engine by gentle driving, increasing to moderate as the engine warms, reduces cylinder fuel wash, reduces blowbye contamination, reduces emissions ( by lighting cat and getting car into open loop ), reduces carbon build up on pistons and reduces fuel usage. According to MkIV forums, it will also make your dick bigger and make you irresistible to super models.

Running a Fuel Injected car on open loop start-up cycle is equal to the old days of running a car on the choke when cold. You want to get it off of the start-up ( choke or open loop start ) fueling curve as soon as possible. Start-up AFR's can be as rich as 10.3-1 ( depending on temperature ) and the gradually decrease as engine temperature rises.

[K20017]

Ok I got ya. But get this, my car does not want to move unless it's fully warmed up. If I start it up cold and try to move, it leans way out, backfires and bogs down. It I finally get it out to first, AFR is around 16 and runs very sluggish. But if I let it warm up, no issue at all. Not sure what is going on

[Holmes741]

What is that knocking sound in the video? I couldn't tell if it was coming from the engine or something else. And what is the MIL for?

[K20017]

Knocking sound is the cam vibrating something in the bay. MIL is evap leak detection

[Chickenman35]

Ok I got ya. But get this, my car does not want to move unless it's fully warmed up. If I start it up cold and try to move, it leans way out, backfires and bogs down. It I finally get it out to first, AFR is around 16 and runs very sluggish. But if I let it warm up, no issue at all. Not sure what is going on

Ok..but that's an entirely separate issue. You have something wrong with your tune. Sounds like it is not enrichening properly when the engine is cold. Cold AFR' should be very rich

What is your tune and have you replaced the CTS?

Edit: MIL for evap leak detection should be checked out. Vacuum leaks generally not good.

[Chickenman35]

Here is a good article showing the various AFR's needed for an Engine during various transient tables. If you're running 16 to 1 when cold you have a definite problem with your fuel curve.

Note: These are for NA motors:

MIXTURE REQUIREMENTS

The proper air/fuel ratio for each particular set of operating conditions is most conveniently broken down into the two categories steady state running and transient operation. Steady state running is taken to mean continuous operation at a given speed and power output with normal engine temperatures. Transient operation includes starting, warming up, and the process of changing from one speed or load to another.

STEADY STATE FUEL REQUIREMENTS

IDLE: Due to the low port velocity and frictional losses Idle mixtures are typically set at a fuel ratio of 1.2 or, expressed differently, 12.25:1 air/fuel ratio. Your motor will idle at stoichiometry (14.7:1) or less than stoichiometry but this is very near misfiring and If operating temperatures are not stabilized at a high level the motor will die. For example, operational fluid temperatures can vary from 150 degrees Fahrenheit to 250 degrees Fahrenheit and Inlet air temperatures can easily vary 100 degrees Fahrenheit. These variations in temperature all necessitate different mixture requirements so it is far better to keep the fuel ratio in the 1.2 region to preserve idle quality and off-idle responsiveness.

STEADY STATE THROTTLE: At a given RPM under steady state load conditions your mixture strength should be a 1.1 fuel ratio or 13.2:1 air/fuel ratio. At this point you will have your peak cylinder or Brake Mean Effective Pressure (BMEP) figures. The development of a base fuel map is generally done around this figure as It is 11% richer than stoichiometry but within the correction range of a closed-loop oxygen sensing system. This allows the base map to be calibrated for maximum power without excessive fuel consumption and still allows the closed-loop operation to self-adjust to 14.7:1 for normal steady state operation.

TRANSIENT FUEL REQUIREMENTS

The principal transient conditions are starting, warming up, acceleration (increase of load), and decelleration (decrease of load).

STARTING AND WARMING-UP: Abnormally or very rich mixtures are required to start a very cold engine. The air/fuel ratios must be progressively reduced from this point during the warm-up period until the engine will run satisfactorily with the normal steady-running air/fuel ratios. Starting or cranking fuel is also a temperature dependent variable with more cranking fuel required for lower temperatures. Air/Fuel ratios on initial start-up In cold weather can easily be 50% greater than stoichiometry i.e. In the 11.0:1 to 10.3:1 air/fuel ratio range.

ACCELERATION: When the throttle is opened for acceleration, thus increasing the manifold pressure, additional fuel must be supplied to prevent misfiring, backfiring, or even complete stopping of the engine. Injection of this acceleration fueling must take place simultaneously with the opening of the throttle. The optimum amount of acceleration fueling is that which will result In the best power air/fuel ratio in the cylinders.

In general this varies with the engine speed and with the throttle position at the start of acceleration, as well as fuel volatility, mixture temperature, and rate of throttle opening. Since partial or slow opening of the throttle requires less than the full acceleration fueling, the amount of extra fuel is usually made roughly proportional to the throttle opening and the angle through which the throttle moves. Mixture strength under these conditions may be as rich as 12.7:1 on warm engines and perhaps as rich as 12.1:1 on cold engines. When an engine reaches normal operating temperature we should not see acceleration fueling richer than 12.7:1.

DECELLERATION: Under closed throttle decelleration fuel must be controlled to prevent rich conditions or lean Induced backfires. This controlled fuel shut-off can be monitored with the digital air/fuel ratio meter. Decellertion fueling should be no leaner than 17.1:1.

[K20017]

It isn't 16:1 on startup, it's around 9-10 then after about 2 minutes it's back up to 14.7. The only time it leans out is when I put a load on the engine and try to move it when cold, it leans way out and bogs down. My tune is Eurodyne 1000cc malfess. Bought the ECU off the tex in 2008. It also doesn't account for the extra displacement or cams.

[Rac_337]

It isn't 16:1 on startup, it's around 9-10 then after about 2 minutes it's back up to 14.7. The only time it leans out is when I put a load on the engine and try to move it when cold, it leans way out and bogs down. My tune is Eurodyne 1000cc malfess. Bought the ECU off the tex in 2008. It also doesn't account for the extra displacement or cams.

its probably leaning out because your at 2.0L now and you're letting a ton more air in with the cams. if you're tune still thinks you are on stock cams and 1781cc then your fueling is probably set for this i would think.

.2L is a ton when it comes to tuning.

I would say all you're fueling tables are off if its not tuned for 2.0 and cat cams. i'd try the wizzard again, get your idle afr set, and go re tune for the new setup from scratch. pita i know...

also you can try playing with warmup fuel enrichment.

my car starts cold around 12.5/6:1, and as it is warming up, goes to around 13:1 or so. after 85 degrees it starts correcting +/-1.5% or so and sits right close to 14.7:1 (floats between 14.5/15:1 really. still working on it)

[K20017]

Can this be fixed through Unisettings or is it something I will have to pay to get fixed. Either way, I have to sell the car by august and I'd rather just wait the 5 minutes it takes to warm up rather than spend X amount of dollars on it.

[jbrehm]

Does anyone actually keep their BT 1.8Ts? Every time I see one for sale it has like 5,000KM on it

[K20017]

I would keep it but unexpected college tuition is forcing me to sell.

I have to just enjoy it while I can.

[Rac_337]

Can this be fixed through Unisettings or is it something I will have to pay to get fixed. Either way, I have to sell the car by august and I'd rather just wait the 5 minutes it takes to warm up rather than spend X amount of dollars on it.

not sure if eurodyne will let you use unisettings...but if it does, play with fuel enrichment on startup and fuel enrichment on warmup. small incremental adjustments.

[AmIdYfReAk]

the tune has nothing to do with unisettings/etc, they adjust the adaptations that's built into the ecu..

have at it.

[Vegeta Gti]

Does anyone actually keep their BT 1.8Ts? Every time I see one for sale it has like 5,000KM on it

going on five yers for my MKI swapped 20v BT

Sent from my SPH-D710 using Tapatalk 2

[18T_BT]

That's actually not a good way to warm an engine. Start it up, then immediately start driving it. Just keep the revs down till you start getting some temperature in the motor.

Yep, you should drive it right away. Check out any turbo engine, even OEM will tell you. I just drove a 996TT and was looking at the owners manual, said exactly that. Of course it says don't beat on it until fully heated up, but definitely start driving right away.

It isn't 16:1 on startup, it's around 9-10 then after about 2 minutes it's back up to 14.7. The only time it leans out is when I put a load on the engine and try to move it when cold, it leans way out and bogs down. My tune is Eurodyne 1000cc malfess. Bought the ECU off the tex in 2008. It also doesn't account for the extra displacement or cams.

That's normal and will depend on many variables. Like cams and intake manifold and barometric pressure and altitude and temperature outside so it will vary. Take any OEM application on cold start and it won't be stoich at first, why do you think we have secondary air injection OEM?


Yes, you can use Lemmi or Unisettings I think Eurodyne released on a while back, not sure what happened to it (probably didn't need it since they released Maestro) but they were all designed by the same person a long while back!

I still have my BT, bought her in 2002 and still driving her now. Thanks Arnold for the great parts and service, without him my car would be a pile of heaping stuff

[K20017]

I know it won't be stoich on warmup but it won't even let me drive it, it bogs down so bad and leans way out. I'll take a video of it next time. Then I'll adjust through unisettings and see if it changes anything.

Then I'll use a mechanical oil pressure gauge to rule out the electronic sending unit.

Then try 5w-30 to see how that helps oil pressure.

[Chickenman35]

I know it won't be stoich on warmup but it won't even let me drive it, it bogs down so bad and leans way out. I'll take a video of it next time. Then I'll adjust through unisettings and see if it changes anything.

Then I'll use a mechanical oil pressure gauge to rule out the electronic sending unit.

Then try 5w-30 to see how that helps oil pressure.

I don't think your oil pressure is a big issue, as info from Bently's supports 100 psi hot readings. But it still wouldn't hurt to double check with a mechanical guage.


Regarding cold bog. As previously mentioned, the Coolant Temperature sensor plays a huge part in the transitional warm up phase. How old is it and is it an old version ( black ) or the new green versions. A bad CTS can cause a lot of mysterious cold running issues.

Also, do check out post #24. That provides a base point for what AFR an engine needs, particularly when cold. Acceleration enrichment curves are an essential point of tuning.

As mentioned, your ECU tune was for stock cams and a smaller motor. You are going to have to manually tune things to make it work properly.

MAF-less tunes are much more critical on how the accurately the program is written, than a car with a MAF. The wide-band O2 sensors are a relatively slow in response time, in comparison to how fast a MAF can detect changes in airflow.

MAF tunes are relatively insensitive to engine changes ( to a certain point..big cams can confuse them ). They will self tune very quickly and very accurately.

MAF-less tunes are much " dumber " programs, with less fast response feedback ( Due to the elimination of the MAF ). Every datum point on the fuel curve and ignition curve has to be spot on. Your tune was not written for a 2.0 liter engine with cams. Therefor you have to modify the tune manually.

IE: If this was a carbed car, and you stroked the engine and changed the camshaft, you would be changing jets and playing with accelerator pump cams and shooter nozzles


So you may be asking...why on earth would anyone use a MAF-less tune on a street car? The main reason is that a MAF cannot handle big overlap cams. They get " confused " by the rapid pulsations in the intake tract. In that situation you have to switch to a speed density program ( essentially a MAF-less tune ) , which is insensitive to low vacuum and intake pulsations. On a Maf-less or Speed Density tune, every single datum point of the fuel curve, boost level, throttle position, coolant temperature and ignition curve is programmed in manually... by extensive testing on an engine dyno. Obviously this only works for one engine specification. Change one single engine parameter...and the whole program can be messed up. Cams, and you guessed it..engine stroking, are the two items that will most require changes to a MAF-less file.

The CTS also plays a huge part in the transitional operation of a MAF-less tune..which is why it is one item that must be checked.