[Reed]

Okay, now I need some serious input.

Took my compression #s today and got the following results:

#1: 82 psi
#2: 144 psi
#3: 155 psi
#4: 154 psi
#5: 142 psi
#6: 140 psi

So I need a rebuild of some sort. What do I do next?

Will this require a full rebuild? If so, would it be better to get some sort of reinforced engine this time around or what?

Thanks,

A

 

[Ranger498]

well #1 is shot you do need a rebuild !

might want to get intouch with a known shop with a good name to do the work and get a warrenty !

 

[Reed]

I am not too far from Powerhouse so I may take it there.

A

 

[msray]

I had this exact same problem on my 97 TT that i bought from a dealer. Good thing for me is that i insisted on a Compression test before i signed the dotted line. Toyota is replacing everthing!!! I get a whole new block. WHat would cause this to happen. I am assuming that when you listed your cycliders you did it backwards and that #6 is really the shot one. THats how it turned out on mine. WHat would cause this to happen in a 97 TT 6 speed with 58k miles. Terrible maintanence by previous owner?? Running the car VERY VERY hard?? ANy input would be appreciated.

MIke

 

[AnArKey]

If Toyota is gonna pay for it, ask for a brand new engine!

If it's your bill, I would suggest getting the motor out of the car and look at it. Maybe the rings in that cylinder are toast, but everything else is fine. In that case, it could be real cheap if you are willing to do the labor. You could resue everything and just replace bearings and rings (I highly recommend Total Seal rings), and do a rehone. Voila! Better than new for less than $200 in parts.

________________________________________________

As for the reason, I have two theories, depending on cylinder:

#1: Fuel rail design. After having a stock rail off the car to look at, I notice the regulator is between the #1 and #2 injector. Fuel does not go all the way across the rail. Rather it returns before getting to the #1. This could cause a fuel starvation problem on the #1 injector.

#6: EGR. Most of the hot gasses introduced into the intake by the EGR system find their way into the #6 cylinder (due to the EGR being in the very rear of the intake). If the EGR propped open during full boost, it could get very hot in the #6 cylinder and melt things.

These are just theories of course. Take them as you will. The first reason has me concerned, as I was hoping to keep my stock fuel system and inject tons of methanol to augment the stock system. This will not offer total protection from a #1 meltdown if my stock #1 injector only injects half of what all the others are injecting.

 

[Grant]

Low compression in 5&6 due to the EGR is definitely a documented problem. IMO everyone should get a blockoff plate for their EGR.

 

[msray]

Ive noticed this mod you mention in the MKIV tech articles. Has anyone done this. What did it entail as far as parts and labor? Did you do it yourself? Thinking about doing this to me new engine to save future problems

Mike

 

[Reed]

For the record, the cylinder that I burned was #6(not #1). I was looking at things backwards. As a result, I would have to conclude that the EGR may have been the problem. The stupid thing is that I did the EGR mod but not the blockoff plate.

A.

 

[AnArKey]

Well that makes me feel better. EGR blocked off right here!

Reed, I'm guessing that your EGR failed and stuck open. You probably melted that piston. Tell us when the motor comes out.

 

[ATLSUPDAWG#2]

Also may I add, that another reason that may contribute to burning up the #6 piston is the design of the intake manifold. If you've ever looked at the rear (right next to #6), it's flat . So, when you're boosting higher than stock your intake charge hits this "Flat Wall" at the rear of the manifold and slams it right down #6, thus leaning it out.
pwpanas came up with a good idea to cut the rear of the manifold (about a 2" portion or so) and weld on an aluminum block that has been machined concave on the inside. This will buffer the intake charge and evenly distribute it.

 

[Spool]

Any pictures of this? My #6 came out with 135-145 40% leakdown while the others were at 160 at 20%. Not too bad but it's under warranty.

While the engine is out, I'd like to put in a 3200 stall TC, mild head work, and fix the intake issue!!!

Thanks!

Also may I add, that another reason that may contribute to burning up the #6 piston is the design of the intake manifold. If you've ever looked at the rear (right next to #6), it's flat . So, when you're boosting higher than stock your intake charge hits this "Flat Wall" at the rear of the manifold and slams it right down #6, thus leaning it out.
pwpanas came up with a good idea to cut the rear of the manifold (about a 2" portion or so) and weld on an aluminum block that has been machined concave on the inside. This will buffer the intake charge and evenly distribute it.