Ok so my 2002 gti is having some boost problems... Instead of hitting boost consistently the boost is fluctuating for example hitting 12 psi then 15 psi and it just hits and bounces back to 0. what could be problem I was thinking bad downpipe, bad waste gate, or bad n75 valve.
View 6 RepliesI have a 2006 sierra 5.3. This has happen twice to me now. This morning it was probably around -5 degrees out started my truck with remote start and it started fine. After running for 15 mins I got in it to go to work. When went to pull out of the driveway I noticed when hitting the gas my headlights getting brighter and then dimmer when not hitting the gas. When I looked at voltmeter gauge and when not pressing the accelerator it was about 12. When hitting accelerator it would go up to 14. It did this for about 15 mins or so stopping and going.
On the way home today it didn't fluctuate. When I got home I tested the alternator with volt meter. It was reading 15.3 volts. From what I read on the internet it says the fluctuation is normal and so is the 15.3 volts. I read 2005 trucks and up have regulated voltage control. Even talks about the gauge fluctuating in the owners manual. I had the battery and alternator tested both tested good. Alternator does have a little noise in it when spinning the pulley by hand. I'm just not convinced that 15.3 volts is normal. The battery isn't original it had been replaced by the previous owner.? Is my alternator possibly going out.
When I give my car some gas my boost gauge fluctuates a lot and doesn't hold, I have an OEM piston style dv revision d I believe, and I have a catch can and also a blow off valve, and I'm stage 2. I was thinking of getting an awe diverter valve?
View 13 RepliesI have recently purchased a c70 t5 which supposedly had been remapped. Anyway this weekend I changed the ICarScan unit and pipework, replaced the turbo vacuum lines and it has had a full service oil,plugs,rotor arm and cap etc. Prior to this it would occasionally pull aggressively and other times not. Now it boost all the time and feels good, however I noticed the boost gauge is now hitting almost 1.5 bar and dropping to about 0.9 bar. What could be causing this. In addition to the above work I removed the nasty badly modified inlet pipe and fitted an original between the air box and turbo. Which connection go where so I can ensure I am correct.
View 1 Repliesso whenever i AM DRIVING AND i go to hit the brakes the car mostly under the hood in the engine jerks abit then smooths into stopping
99 Jetta GLS 2.0
I bought some coilover for my mk4 Jetta, and the two front coilover just don't seem write, they are sticking way to much from where they need to be at, and they are hitting my hood..
View 24 RepliesI know this isn't the usual ticking of the injectors and I believe it's to fast to be a lifter tapping. I believe it's the camshaft chain hitting against the valve cover. I took the valve cover off and the chain is still tensioned tightly so it makes me wonder what this could be..
View 1 RepliesI installed 2 new axles and replaced the upper motor mounts in my car. Now when I turn to the right the left front tire is running against the coilover and making my car vibrate. I put a 5mm spacer to give it some clearance but it didn't make much of a difference. What could be wrong?
View 2 Repliesmy car into VAG COM and since then it hasn't boosted past 4 lbs. it has Revo stg 2, K04, aftermarket side mount, full exhaust and a couple other bolt ons. Before the car was spiking at around 23/24 lbs. after pressure testing the system I found that the turbo inlet pipe was lose, so I tightened it. Still no change. I tried holding the battery terminals together for 10 minutes to reset the ecu and I also tried clearing the codes through a handheld code reader. No codes even come up anyways for this. The car is a 1.8T.
View 4 RepliesSo my 2001 1.8t Golf is having some issues holding boost. I have a Gonzo stage 2 tune, CTS FMIC, Forge 008 Diverter, Silicone inlet and MagnaFlow Exhaust. I've also done the whole Evap, SAI delete and installed a catch can.
Starting in 2nd or 3rd at WOT the car spikes up to 18psi and then progressively loses boost throughout the rev range. Close to redline the boost drops to 5 psi or so. It seems to be dependent on the revs. In fifth gear the car holds 18 psi much longer as the revs don't increase as fast.
There are no CELs. I've done multiple leak tests starting at the air box and plugging the pcv/catch can system as well as at the compressor side of the turbo. None of the tests revealed a leak anywhere in the intake system. However, when I stuck my ear very close to the valve cover I could hear what sounded like a very small air leak coming from inside the valve cover. I took a look at the wastegate actuator and it seemed fine, no play in the rod, no loose bolts and to move it just requires enough force to compress the spring and it returned to its original position.
My thoughts are that it could be a fueling issue or turbo in the process of dying maybe.
Just noticed today that I have a slight drop in boost. Normal boost is 1.5 bar but today it is running slightly lower boost and does not have the same pull through all the gears.
2001 mk4 1.9 tdi golf
I just recently notice a whistling noise when I hit boost. I'm not sure but it sounds like it is coming from my gauge. I'm not losing boost pressure. I do have a glow shift gauge. The most recent install was the TIP which I clamped on to the turbo but I'm wondering if it isn't on tight enough.
View 2 RepliesI was riding along today everything running fine then I came to a stop sign and when I pulled off my car wouldn't run 10 psi of boost it was only running 5 psi so I when to a buddys checked everything over and all my piping looked fine so I went up the road and everything was fine so when I started going home it did the same thing pulled of shut the car off pulled off and it was fine again.
View 5 RepliesI think my stock DV is going bad, my car makes a weird noise under boost?
1. Only happens when first starting the car after it has been sitting for an hour or a few. (not overnight)
2. Does NOT happen when first start in morning.
3. Goes away after like 5 minutes every time and the normal WHIIISHH sound comes back like it should when I step on the gas.
4. It does not make the sound at idle.
This recording I made was of my car being revved up after it sat for one hour.
[URL] ...
Replaced my coil packs/sparks, and just got around to changing my N75 valve today. The rough idle issue is gone but now when I go WOT it boosts but goes from 15psi-12-13-12-14-12...etc. I've checked and there are no boost leaks. I do have a CEL saying I need a new bank 1 sensor 1 Oxygen sensor. If it is that, why did this problem arise as soon as I changed the N75 valve and wasn't present earlier?
View 1 RepliesI was having an issue with my car not going into boost so I plugged my code reader in and it had 2 codes 1 was p1200 n249 malfunction and the other was diverter valve malfunction so I did the quick easy one and got a new factory diverter valve but it still doesn't go into boost and still reads p1200 n249 what do I need to replace or should I do the n249 bypass it's a bone stock jetta 5 speed.
View 5 RepliesI just got done with a complete engine rebuild on my 02 1.8t jetta, had everything hooked back up and went to start it for the first time and it wouldn't. I went back looking for loose connections, nothing. Worked and banged my head for a day or two, I had fuel and spark but couldn't get it to fire. Finally I "choked" the intake to see if it was getting too much air and it fired right up. I unplugged my map sensor giggles and it starts up perfectly. I then hooked everything back up and what do you know it starts up and runs fine, but if I plug the sensor back in it kills the motor after about 10 seconds of running and won't start until I unplug the map again.
Car runs and drives but wont boost over wg pressure but that's probably because sensor itself is unplugged. I just wanna know what could cause it besides the sensor itself being bad. I ordered a new one waiting for it to get here (hoping it fixes the problem).. And I'm talking map (manifold absolute pressure) not maf (mass air flow), just in case people are confused.
I got a Mk7 in October and my Mk4 has unfortunately been parked since. I started it and let it idle to warm once a week or so when I went on Vacation for 10 days. Before going on vacation I moved the car and after warming up everything seemed to be normal. Unfortunately I neglected it once I got back and haven't started it since the beginning of December. I'm selling it here soon and so went out to spruce her up tonight and upon trying to start the battery was dead so a buddy came over and jumped it.
It started right up but immediately was idling funny which I assumed was because of the cold (it's 25 degrees F tonight and has gotten in the negatives in the past few weeks due to snow storms). I shut it down and checked the fluids which were all pretty low especially the oil due to a small leak. So I topped off the all the fluids and started it again and let it idle to full warm.
I decided to take it for a drive around the block and it was still driving pretty rough, no knocking or anything but the engine was "sputtering" and the CEL was on and flashed when I gave it gas. I'm running stock boost so my gauge usually reads around 12psi but is now only going up to 3-5 psi and the vacuum is only at -15 which i think used to idle at -20. I drove it to the gas station and filled it up from a little less than a half tank but it's still running the same and there's a slight burning smell from the exhaust.
I was worried it was my turbo but it was perfectly fine a month ago. I was thinking of throwing some Seafoam or Heat.
Okay, here's the car
AWP 1.8t mk4 GTI.
- stock DP
- Forge 007 splitter adjusted 25 clicks
- Swiss cheese stock intake with k&N high flow
- APR stage 1 93 tune.
My boost gauge is currently reading peak of about 15-16 psi. I replaces some vacuum hoses that appeared to be worn, and to no avail. I have no CEL, and no codes thrown at all. This sound like a boost leak.
I just replaced my my k03s with another one with only 20k on it. After I did this, I noticed a loud screech sound when in WOT. The screech lasts a little bit after i left off the gas when revving in neutral. I've been doing research on here, and I've read that it could be a boost leak somewhere or even the turbo dying. The shaft play is minimal though.
View 17 RepliesRecently got my VCDS USB cable that I can use on the newer 1.8T Jettas and I haven't found a measuring block for boost or MAP data. My Scan Gauges don't give a MAP data field either for the 1.8T engine, while it does for the TDIs.
Where do I find this data? Surely the ECU monitors boost?
Couldn't find anything while hooked up to the Buddys Passat 1.8 that we did a TB and thermostat on yesterday.