Rebuilt engine not going very fast

[isbre]

UPDATED, see page 4 for latest development

A while back the skirt of one of my stock pistons broke off @ stock boost pressure leaving me stranded. (still trying to figure out how this could happen) Not getting any help from the both warranties (factory and extended protection plan) because I imported it back home I had to deal with it myself. After saving up money and waiting for parts and whatnot for the longest time I got it up and walking again. Problem is that I want it up and running again, now my parents old 90HP diesel can keep up with my MSP (it does have a psi tuner chip installed, but still is normally slower)

The CEL is lit with trouble code P0106 (MAP/Barco circuit range performance) but that lit up before I replaced the hotpipe fixing the turbo hesitation that was there because the recirculation nipple was broken off.
The boost pressure seems normal spiking at 6psi and stable at 5psi up to about 4000rpm where it goes down to 4.

When I put pressure on the car like driving uphill I hear a whistling noise from about 8 vacuum and up. I remember this sound and had it repaired in USA but when I asked the dealer about what they replaced the guy told me the 'wastegate gasket' - hopefully not a newb question; but what is that? (is there a gasket in the middle of the wastegate maybe)

Also before the engine really came to life at 4000rpm and I could just floor it up to 6000rpm if I wanted to. Now it's starting to come to life like before, but at 4500rpm the torque is almost entirely gone and it even has problems passing 5000rpm, it acts almost like turbo hesitation.

Also before my car broke down idle vacuum was 24, (It went down from 22 after a warranty repair dealing with the whistling sound)
Now it's only 18-19, is that the new pistons maybe?

Mod list:
Forged engine with Pauter rods, Wiseco pistons (9.0:1) and cometic headgasket (standard thickness)
Mazdaspeed lightweight flywheel
extigy stage 1 clutch
Injen CAI with K&N filter
MPI tuner
Reflashed ECU turbo hesitation October 2006
AWR front and rear engine mounts 88 durometer
(DaveB rings and upgraded stereo)

Anyone know what my troubles might be?

EDIT: Changed exhaust studs and gasket and the whistling noise is almost entirely gone, low end torque and boost seems normal, still having troubles at high RPM, wire harness connected wrong? chack out post 9

05-12-2010: FAULTY PART FINALLY FOUND!, see post #54

 

[Jaysanooch]

I don't know if I can help but I do find a few things weird though.

Boost: Spiking to 6psi and holding to 5-4psi sounds low. Norway should be cold nowadays so I would think you would be spiking to 7-8psi and holding the very least 6psi.

Try checking/replacing your wastegate actuator...it might be stuck on slightly open. I replaced mine to an ATP turbo WGA

Vacuum: 18-19 vac doesn't sound right either...most of us are in the 20-24vac. You probably have a vacuum leak you are not aware of. If your running the stock IC pipes still...there must be half a dozen areas they typically leak.

Make sure everything is tight...EVEN if your running forged pistons, vacuum shouldn't change I believe. I run forged pistons at a lower compression then stock and my vacuum at idle reads -20vac and -24vac when I let off the throttle in gear.

 

[isbre]

It's averaging 5 degrees celcius here now, that's about 41 fahrenheit.
It's never been much higher than 5 psi anyways. I can of course try to get a new wastegate, but I don't want to do that before I now for sure. If I do get a new WGA I think I will try to get a bigger SMIC and better pipes and amp up the pressure a bit, but I was hoping to get it working now and get a GT28RS when I can afford one.

If I let the throttle in gear it goes down to about 22-25 vacuum (depending on speed). I am running the stock IC pipes still but all the vacuum lines is replaced with silicone ones. In situations where I just press the throttly slightly to avoid fuel cut I read about 20. In my eyes it looks to be OK on the road. (But I might of course be wrong)

Something I did forget to mention in my first post that it idles rather high; about 1000rpm warm. Sometimes it cannot decide either. It may idle at 900rpm, I press the pedal and it goes down to idle almost 1100rpms, then press the pedal again and I may get another readout, but it is always in the 900 - 1100rpm range.(uhm) It often stalls for a secind or two at 1500rpm on the way down too.

When I start the engine cold it idles at almost 2000rpm thie first minutes before it gets heated up, but it did that before too, I think that is normal.

 

[Jaysanooch]

Not only the vacuum lines but also check for leaks on all IC piping and connections to the smic and bpv.

Get some carb cleaner and spray around the piping, connections etc and see if your idle changes. That would indicate a leak you can't see.

The boost still sounds low and may not be the WGA itself but somehow get under there and check to see/feel if the internal actuator mechanism on the turbo, opens and closes smooth. It might be corroded keeping it slightly open. Just throwing some idea's.

 

[isbre]

Get some carb cleaner and spray around the piping, connections etc and see if your idle changes. That would indicate a leak you can't see.

The boost still sounds low and may not be the WGA itself but somehow get under there and check to see/feel if the internal actuator mechanism on the turbo, opens and closes smooth. It might be corroded keeping it slightly open. Just throwing some idea's.

Thanks for the ideas

I don't think I will find the time before the day after tomorrow, but I will see of I can get some. Just spray on the outside of the piping?

But I have no idea how to check the internal actuater mechanism on the turbo?
Is that the little handle that is connected to the wastegate?

 

[Jaysanooch]

Thanks for the ideas

I don't think I will find the time before the day after tomorrow, but I will see of I can get some. Just spray on the outside of the piping?

It's not urgent..but when you do, yes just spray lightly on the outside of pipes near connections.

But I have no idea how to check the internal actuater mechanism on the turbo?
Is that the little handle that is connected to the wastegate?

Not the easiest of place to get to..unless you put your car on a lift. Here's a picture for you..thanks to someone on here I copy/pasted from. The arrow in yellow shows the area I'm talking about and 2nd picture circled in blue.

 

[isbre]

I did some more checking today since I had the opportunity to borrow a carlift at a shop.

I didn't find any leaks, and the idle was unchanged when I sprayed carb cleaner on all vacuum joints I could find. What I did find a almost loose electric cable leading to a valve or something with vacuum lines attached. I don't know what it is so I attached a pic of it. Reataching that gave me 22 Hg vacuum cold @1500 RPM and 20 Hg warm @900-1000RPM. What is strange is that I get 22 Hg going from driving to idle and it goes up to 20 Hg when it hits idle.
On my way home I let off the throttle going downhill @ around 55 Mph and then my boost gauge showed me 27 Hg vacuum.

Now onto my WGA findings:
I blew into the hose going to the WGA and didn't hear any air escaping, but afterwards I borrowed a handheld vacuum pump and discovered that the pin going from the WGA was completely static, it didn't move at all. Does that mean that it would probably be a good idea to change the WGA?
And could a stuck WGA affect the idle RPM?

 

[livelyjay]

The WGA isn't activated by vacuum which is a low pressure. It's activated by boost which is high pressure. If you blow into the line going to the WGA, if you can actually push a few psi with your lungs, you may be able to get it to move. A stuck WGA would not affect idle. Idle RPM is dictated by a few things, and the first thing I would check is your throttle cable. There is an adjuster screw at the throttle body that may need to be tightened/loosened to get your idle right.

 

[isbre]

Wire harness connected wrong ??

Hi again

Thanks for the help so far.

Still having troubles at high RPM. After 4500 RPM it just bogs down, almost all power is gone and I have problems reaching even 5000 RPM.
In neutral I reved it up to redline once and at 6000RPM is was a loud high frequent sound like someone have dropped pennies in the engine, is that engine knock? - Not doing that again any time soon for sure.

I was thinking back to the time when everything was assembled back in my car. The guy who helped me was 100% sure that every cable was connected correctly, but shortly after I connected 3 plugs he had left out and changed 2 vacuum lines placed incorrectly. I did that from an old photo of my engine bay. Trouble is that the pic dosn't show everything and I suspect that a cable is connected wrong.

On the drivers side of the engine there is a cable that stands out as it is ending up in one single plug where all others ends up in several. This plug may be connected at least to places:

• The primary O2 sensor
• A wire that runs further down the engine bay (secondary O2 sensor?)

Anyone know which one is correct? (or is it supposed to be somewhere else entirely?)

 

[dstmsp03]

might check your intake, make sure its not leaking..

 

[Fudgie]

Have you double checked your cam timing????????

 

[mikeski]

yea, could be timming.

 

[isbre]

might check your intake, make sure its not leaking..

I have checked the joints on the intake (injen) with carb cleaner, didn't find anything wrong there, but there is a little crack in the hotpipe. When I was in USA (Covered by the warranty) the entire reciculation nipple broke off and the engine still had no problems with high RPMs. Don't think a tiny crack will criple the engine this much, especially when it is normal at 3500 RPM and full boost. (which is wasn't with the recirculation nipple broken off)

btw: Looking for a new hotpipe (mandrel bent aluminium or Samco intecooler hose) anyone got any f/s?

Have you double checked your cam timing????????

When the engine first was re-assembled the timing belt was very off. The engine barely ran at idle but fine at higher RPMs. I had it towed it to a Mazda dealer and they corrected the timing belt position.
The timing map in the MPI dosen't tell me much, so I haven't checked that out. I'm thinking of taking it away and replacing it with a custom tuned Unichip since I don't have enough knowledge to tune the MPI myself.
(I kept in my car bacause the guy that helped me told me he could tune the MPI afterwards, but after a lot of "small mistakes" like the timing belt position and vacuum lines I just didn't trust him enough to let him tune the thing)
Problem is of course that I didn't install it myself and that makes it harder. I don't want to solder two wrong cables together and I don't know if any of them are shielded.

I know you talked about timing retard earlier, my guess would be that the spark plugs fires too soon at higher RPMs but it had no problems reaching redline before, and has exactly the same tune now.

Hope that answer your questions

 

[MAZDA_SPEED]

post video clips...idle..running..driving..
i want to see whats going on..

 

[isbre]

I'm actually not driving it more than I absoultely have to because I don't know myself what's going on, but if it will help I will do that - tomorrow, right now it's dark outside and way past bedtime...

Would be nice to know the correct placement of that cable in post 9 first though. (if it really is in the wrong place the ecu doesn't get the correct signals from the primary o2 sensor, guessing that is problematic if that's the case)

 

[isbre]

The original file is 3.4MB and in mpg format. Too large for an attachment here. Converted it to wmv format to upload it, sorry about the tag in the middle though.

I uploaded it to photobucket without the tag.
http://s299.photobucket.com/albums/mm303/isbre/?action=view&current=2nd_gear.flv

All I have is a old digital still picture camera, so this is not the best quality, but it sill works I guess. Sorry about forgetting to pause the cd.

This is a rather hard acceleration in 2nd gear, but not full throttle. You'll see that it absolutely refuses to go over 5500RPM under load (I didn't let go of the pedal until the last seconds of the video) That horrible noise you hear at the end is almost like what I hear louder at 6000RPM if I rev it up to redline in Neutral.
I was alone and shifting gears and holding a camera and steering wheel is hard. If I would have managed to switch to 3rd you would have seen the car pulling normal uo to higher RPMs and then the exact same thing.

I can make a recording of engine start, idle or whatever if it will help you help me find the problem.

 

[Jaysanooch]

It's seems as if your not running on all 4 cylinders. It's gotta be a spark or timing related problem.

 

[ItsSlow]

Pull your plugs and take pics of them so we can see what they look like..

 

[isbre]

I pulled the plugs and the plugs in the picture is arranged in the same configuration as in my engine. (Cylinder 1 is to the left, Cylinder 4 is to the right)

The second pic shows the cable I am unsure if is connected correctly, it seems that it may be connected to the primary o2 sensor instead.

 

[Jaysanooch]

The wire is hooked up right...maybe just routed differently. The plugs look good, I'd check the gap though. They should be around 0.032.

You say you have a cel light right? And I think you said you know which one it is...BUT have you re-scanned the car recently to see if you have other codes?