ClubWRX Forum banner

1 - 18 of 18 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
Hey all! First time post here, I'm hoping I can get some sound advice, I'll give as much info as I can on the situation, I don't have much knowledge with the Flat 4/Boxer motor design and engineering for the WRX/STI.

I recently bought a 2006 WRX outright with 167k miles and I am the 4th owner. The person I bought it from did mention it has a couple upgrades; Upgraded higher CC Fuel Injectors, an "STI Turbo", and it does have an STI Intercooler, AEM Intake, as well as a full Invidia Exhaust, and a COBB Tuner/Tune. The car runs rich, I can tell, it stinks like a lawn mower, makes sense especially with all the upgraded air mods and a tune and bigger injectors.

I had the previous owner do a PPI at a local Subaru dealership to get an idea of what needed replacing. Leakdown and compression test was fine and they said the car is solid. I replaced the Spark Plugs, Oil Pump (11mm, not 10mm), Water Pump/Timing Belt, Front Suspension Bushings, front L/R CV Assemblies OEM, and 4 struts.

Car ran fine when I got everything installed by a local shop, however, they used the wrong oil plug and I had an oil drip.

When doing the PPI, Subaru techs didn't drive the car fast enough to notice that there was a grind going into 5th gear, so I took the Subi to AAMCO and had them fix the grind. I received the car back and it seemed to be running fine, there may have been a slight decrease in torque/throttle response but nothing that was noticeable or unusual, I let it go.

After that was done, I went to a local reputable independent Subaru tech shop to get a proper oil plug. I asked them what oil they recommended and they said they "ONLY RECOMMEND SHELL ROTELLA T4 EXTREME TEMP 5-40 DIESEL OIL, cause it's a turbocharged engine" Which seemed unusual but given their reputation and experience I followed their advice and did the oil change about 2 weeks ago. They had everything from Forresters and Xtreks to old and new WRX/STIs with and without mods and their reviews are all stellar. So I trust/ed them.

As expected, the car had less power and worse gas mileage. I live in Phoenix, AZ, mind you, and it's hot as heck this time of year.

But things quickly have declined. The idle sounds different, the throttle response is gone. The exhaust sounds different. The car was actually bogging and cutting out (spool included) under acceleration and even pops out white smoke (unburned gas) occasionally. Im afraid the engine was knocking though I dont exactly know that sound, and I've been consulting my father for advice.

I figured the oil was just too much so yesterday I switched it back to High Mileage Castrol CTX 5-30 weight. I also noticed an usual chemical smell yesterday, almost like isopropyl or something very fumey, but I haven't smelled it since. It was random.

Today It's a little better but the throttle and torque is just gone. I don't feel as much boost at all, like the motor isn't getting enough air. I get on it and I get small cuts in power but not as bad as the old oil I'm thinking at this point the plugs are fouled so I'm trying to run higher RPMs to try and clean them out and added a fuel system cleaner to help it along.

But I'm starting to wonder if boost is being lost somewhere. I am planning on running the COBB monitor to see where the boost pressure is and if there's a loss in pressure somewhere. I don't know if during the transmission repair of parts of the boost system were disconnected, or if this REALLY could be caused by running heavier oil and where to look.

I'm concerned about running rich for too long and hurting the motor. Any advice is helpful. Getting worried about costly repairs tho my father seems to think it's not dangerous in the short term.

Thanks guys.
 

·
Moderator
Joined
·
11,254 Posts
Hey all! First time post here, I'm hoping I can get some sound advice, I'll give as much info as I can on the situation, I don't have much knowledge with the Flat 4/Boxer motor design and engineering for the WRX/STI.

I recently bought a 2006 WRX outright with 167k miles and I am the 4th owner. The person I bought it from did mention it has a couple upgrades; Upgraded higher CC Fuel Injectors, an "STI Turbo", and it does have an STI Intercooler, AEM Intake, as well as a full Invidia Exhaust, and a COBB Tuner/Tune. The car runs rich, I can tell, it stinks like a lawn mower, makes sense especially with all the upgraded air mods and a tune and bigger injectors.

I had the previous owner do a PPI at a local Subaru dealership to get an idea of what needed replacing. Leakdown and compression test was fine and they said the car is solid. I replaced the Spark Plugs, Oil Pump (11mm, not 10mm), Water Pump/Timing Belt, Front Suspension Bushings, front L/R CV Assemblies OEM, and 4 struts.

Car ran fine when I got everything installed by a local shop, however, they used the wrong oil plug and I had an oil drip.

When doing the PPI, Subaru techs didn't drive the car fast enough to notice that there was a grind going into 5th gear, so I took the Subi to AAMCO and had them fix the grind. I received the car back and it seemed to be running fine, there may have been a slight decrease in torque/throttle response but nothing that was noticeable or unusual, I let it go.

After that was done, I went to a local reputable independent Subaru tech shop to get a proper oil plug. I asked them what oil they recommended and they said they "ONLY RECOMMEND SHELL ROTELLA T4 EXTREME TEMP 5-40 DIESEL OIL, cause it's a turbocharged engine" Which seemed unusual but given their reputation and experience I followed their advice and did the oil change about 2 weeks ago. They had everything from Forresters and Xtreks to old and new WRX/STIs with and without mods and their reviews are all stellar. So I trust/ed them.

As expected, the car had less power and worse gas mileage. I live in Phoenix, AZ, mind you, and it's hot as heck this time of year.

But things quickly have declined. The idle sounds different, the throttle response is gone. The exhaust sounds different. The car was actually bogging and cutting out (spool included) under acceleration and even pops out white smoke (unburned gas) occasionally. Im afraid the engine was knocking though I dont exactly know that sound, and I've been consulting my father for advice.

I figured the oil was just too much so yesterday I switched it back to High Mileage Castrol CTX 5-30 weight. I also noticed an usual chemical smell yesterday, almost like isopropyl or something very fumey, but I haven't smelled it since. It was random.

Today It's a little better but the throttle and torque is just gone. I don't feel as much boost at all, like the motor isn't getting enough air. I get on it and I get small cuts in power but not as bad as the old oil I'm thinking at this point the plugs are fouled so I'm trying to run higher RPMs to try and clean them out and added a fuel system cleaner to help it along.

But I'm starting to wonder if boost is being lost somewhere. I am planning on running the COBB monitor to see where the boost pressure is and if there's a loss in pressure somewhere. I don't know if during the transmission repair of parts of the boost system were disconnected, or if this REALLY could be caused by running heavier oil and where to look.

I'm concerned about running rich for too long and hurting the motor. Any advice is helpful. Getting worried about costly repairs tho my father seems to think it's not dangerous in the short term.

Thanks guys.
It should run rich, that's a problem. Clean the maf sensor, do a smoke test for boost and vacuum leaks, coils, plugs, etc. You say you have a cobb accessport, have you run a datalog?
 

·
Registered
Joined
·
11 Posts
Discussion Starter #3
Hello, thank you for responding.

and I'm sorry are you saying it should run rich? Or shouldn't? Got confused on your answer.

I just got back from a drive, the Accessport showed almost CONSTANT vacuum negative boost pressure. I think I maybe hit 2lbs at one point in time but it's almost always negative.

I have heard to clean the MAF sensor, will do that.

I'm unsure how to do a smoke test, I'll look it up.

And no I haven't run a datalog.

This is my first car with modifications and an Accessport tuner, since it all came with the car I unfortunately know absolutely nothing. About how to use them and monitor them.

I had a previous 2017 WRX but it was bone stock and gave up the car payment to aquire this.

At idle I do hear a knocking / rattling sound near the front right of the cabin where the turbo sits by the passenger foot well, but the Cobb Tuner doesn't show knocks when I monitor for them.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #5
I will try to record it, it seems to be intermittent because when I got home it was no longer happening... Ugh

I was hoping it was a missing C Clip on the actuator arm, and where the arm meets the turbo housing there is this rusty little ring on the bottom side that was loose which I tightened.... Not sure if that will fix it.

Nothing else in the area seems to be loose or missing. The tubes and connections all seem fine.

Starting to wonder if it's a wastegate issue.

I've attached a photo
322744
 

·
Registered
Joined
·
11 Posts
Discussion Starter #8
AF Learning, Boost, Boost Error, Calculated Load, DAM, Dynamic Adv. Degree (?), Feedback Knock, Fine Knock Learn, Ignition Timing, MAF, MAF Voltage, Throttle Position and Wastegate Duty.

Wasn't sure if there was a way to pick parameters, that's just what it defaulted to.

I can send it privately if you want to see it.

Thanks again for responding
 

·
Moderator
Joined
·
11,254 Posts
Stop everything you are doing with that car you have serious issues.

Your car is pulling global timing, a lot. That's the cause of your issues. You need to find and diagnose your misfire.
 

·
Moderator
Joined
·
11,254 Posts
Care to explain a little more?
Your dam is the global engine timing. It has been retarded by a great deal. It should always be 1. Anything less means it's pulling timing to prevent knock.

I would perhaps begone starting diagnosis for issues that may cause knock like plugs, coils, boost and vacuum leaks, exhaust leaks, and sensors.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #17
Dang... Well, upon some surface Google searches, others are reporting global timing issues from the Gates Water Pump/Timing Belt system which I got from Wrally Sport Direct and put on the car when I bought.

Have you heard of any similar issues? It would make sense....

I'm taking it to a mechanic on Monday, just want to be sure to list all the areas to look at. Really sucks to hear it's such a deep issue but better than losing the motor out of ignorance.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #18
Sorry it's been so long guys.....

So....

What apparently was the issue, a combination of both the tune on the car when I bought (probably the culprit) it and a faulty/damaged injector.

One injector (Cylinder 3) had broken, flooding the cylinder and head and creating all the bogging and boost issues. Unfortunately 1 single injector isn't a common sale item so I had to order a whole new set of 4 of the same model (COBB Top Feed 1050x) to install.

Unfortunately I had to replace the valve in cylinder 3 as well as th valve became bent from the flooding and misfiring, further complicating the problem....

Everything was handled properly and installed with new gaskets and I also got a new tune from a reputable location and since then everything about the car has been great.
 
1 - 18 of 18 Posts
Top