4agze owner/expert help

[Tom86]

Hi everyone,

Just finished the 4agze conversion for my sprinter. It a MAP AE92 with Evo front mount intercooler.

The car doesn't seem to be running as it should. Firstly it idle at 1500rpm, secondly it doesn't seem to have much power only seem to pull in first and second and i'm using a 4.3 diff?? in third gear when I floored at around 3500-4000rpm (peak torque??) it would make this rattle noise and grandually pull then take off. Is this normal? (feel kinda like my old 4ac with more push) My gf even said that the car sounded like crap when power come on :huh:

After reading about how good 4agze this and that I was expecting this instance throttle response from the engine, but instead I get to me a faster 4ac. I'm I expecting too much?

I haven't got a boost gauge to see how much boost I'm running, assuming its stock how much boost should I have?

Any help would be much appreciated.

Thanks guys

[Ben Wilson]

That's definitely not normal, I'd be checking for a massive boost leak or possibly that your supercharger isn't engaging.

[YLD-16L]

it would make this rattle noise

Could it be that the bearings in the SC are completely fubar Ben? Might be the noise and could effect the tolerance between the rotors in the SC??? Or I could be completely wrong

[Ben Wilson]

I'd guess that if the bearings were that gone, that the charger would seize..

They could be on their way though..

[Tom86]

The more I think about it the rattle is more like the engine timing is too advance. Would this explain the lack of torque? because the engine doesn't seem to have that pull from idle everyone talk about?

[YLD-16L]

The more I think about it the rattle is more like the engine timing is too advance.

Is the rattle sound actually pinging? Might want to get that checked out then before you do any serious damage.

[Ben Wilson]

I concur - It's always tricky trying to diagnose stuff via the web. There is obviously something horribly wrong there (unless you had a really good 4AC)..

[Tom86]

I will check the timing when I get home. I didn't really want to play with the timing as I am unfamilar with this engine ie using coil pack and no distributor. How do you adjust the timing on this engine?

[Ben Wilson]

You move the CAS* just like a distributor.

* - CAS = Crank Angle Sensor, mounted on the front of the head on the exhuast side, looks like a distributor without leads.

[mullett]

/\_______/\ What he said...but with a timing light If you're not too familiar with using one, just get your local garage to do it, should see change out of $50...

RM.

[inertia]

I'd guess that if the bearings were that gone, that the charger would seize..

They could be on their way though..

Mine has somehow continued to live, whilst making a god awefull bearing noise every once and a while... it's quite wierd how it comes and goes...

onto the original poster:
My gze was very lackluster when we first got it running and it ended up being that the exhaust cam timing was a tooth out... even though we'd doubled checked it as per the manual when the engine was on a stand... worth checking the cam timing before checking the dynamic timing in my opinion.

[Vios-GT_07]

yeh definitely.. check everything fuel (do u have a proper electric fuel pump? like from a VL turbo or something), spark (are your plugs and leads good?) and air.. i.e. your air intake is not blocked or dirty or anything like that..

then i'd go into specifics like looking at your timing, cams and cam gear position (i.e. not off a tooth or something), and also if your timing belt is worn and causing the problem.. and also have a look at the super-charger.. see if it's engaging (it's a magnetic clutch so u can see if it's engaging or not.. even by-pass it to see if it clicks") and also if it whines and u have boost when it's engaged.. this is where a boost-gauge is handy

then i'd have a look at your oil pressure, enough oil, water, HG, and yea ECU.. 1500 rpms is a tad too high, maybe that's a clue as to your retarded performance? hmm..

[Tom86]

Hey guys,

Thanks for all the suggestion. While I was trying to check the timing on the weekend I opened up the diagnostic terminal and it seem to be full of some sort of oily greasy crap in the plug, but then I remember seeing the same thing on my old 4age what's the deal with that?? is it some toyota special grease crap to stop you from accidentally shorting out terminal or something

Anyway, was just reading this thread about other toymodder 4agze that didn't make much power and the cause of this was the fuel pump.

I'm currently running a standard fuel pump from a 4age do you think this could be my problem? Does the 4agze really need that much fuel to run?

[The Witzl]

1/ The grease you speak of is a special compound to avoid corrosion of the bare terminals inside the diagnostic port - it's supposed to be there

2/ The stock 4age fuel pump will be plenty for the gze.... unless you have a half fucked pump.

3/ I would check your base timing by shorting out T1 to E in the diagnostic port, and then starting the car. With a timing light, check the timing, and adjust as necessary to get it to around 10deg BTDC compression (IIRC)

[Ben Wilson]

2/ The stock 4age fuel pump will be plenty for the gze.... unless you have a half fucked pump.

I concur - I'm getting 130kW out of mine with a stock pump.