Posted on the GTO site as well HP Tuners....sorry for the redundency just hoping to hit some knowledge base somewhere!!!!


Finally got around to getting the Alky system installed....that is the good thing...I think...

So I go out for a little test drive, warm it up and wind up to around 4000 rpm and 3 psi or so just to check the "ON" point of the ALKY. The system seems to work fine.....unfortunately car started to run very badly after a couple of hits with the 50/50 mixture. car is throwing P0300 (?) misfire detected code and its running like it as well. also started to ping...although HP tuners didnt show any KR???? So back at the garage I go. strange thing is by placing my hand on the exhaust tips the left tip (routes to the right hand bank) is hardly putting out any airflow, I can easlily cap it off with my hand. the other bank is putting out what one would consider normal

considering I just installed a cam I was thinking the worst.......ie valvetrain something broke. So I removed the valve covers, and spark plugs. the plugs on the RH bank looked fouled, confirming the exaust issue. I was convinced there was going to be an issue with pushrods or rockers etc.....nothing was evident...everything going up and down like it should. double checked the torque on the rockers....all good.

Next I did a static compression check with the following results.

1. 150 2. 145
3. 160 4. 150
5. 155 6. 135
7. 155 8. 150

Not really sure what is going on with #6, I tested that one 3x came up with the same results??? In any case that is not enough to be causing my problem.

with nothing obvious I reinstalled the OEM spark plugs and put her all back together...same problem

So either I have a blockage in the RH bank exaust.....or the entire RH bank is not firing correctly. Scanning with HP tuners comes up with nothing other than the misfire code.......

Looking for Ideas guys

 

that code could come from the cam. any more info. when did you install the cam. what cam?

 

the cam is an EDC design 224/232
problem is not cam related (at least don't think so) she was running like a champ until the alky spray.

it seems to be the entire RH bank is not firing as it should!! although headers and exhaust is hot to the touch, just no flow!!! This is what drove me to the compression test...thought for sure I had valves hanging open or worse....but I am getting compression, when the plugs were removed they were fouled but not wet nor did they smell of fuel...

 

What about plug wires. Had the same problem on a friend's SS pickup with a Radix. Plugs looked fine, changed plugs, and wires, and all seems to be fine, so far.

 

The stock gto exhaust system doesn't have an x or h-pipe?

 

Wild guess, the alky will clean out carbon form the engine. Maybe a chunk of something came loose and got caught in a valve. In the Buick GN world the alky motors look like new inside when they are torn down.

 

Have you tryed disconnecting the Alky-Meth, to see if the problem goes away. Are you sure you are not pulling fluid uncomandly. I know it is not desinged to spray untill under boost, but there might be some leakage down low.

 

clog up a cat?

 

The "H" pipe that is there is nothing more than a cross support. When installing my wideband sensor we looked down in there....blocked off completely.

 

I will be pulling the tube out this morning as well as swapping o2 sensors....hopefully it is something as simple as this.

 

Most decent kits come with a "test spray" button. I've revved my car up before and test sprayed without issues. However, I have Denso O2 sensors. It's possible you soaked the O2's, as well as, the plugs with water and alky (if you mixed it). If you did not mix it, I would try mixing the alky with water either 70/30 or 50/50 ( alky to water). Change your plugs and 02 and see how it runs again.

 

Update:
swapped front and rear O2 sensors.....problem still on the RH bank.
Swapped coil packs.....no change.

 

I had a random misfire problem recently and after checking and replacing everything I found out it was the brand new plugs I had just put in (autolite). So make sure you're running ac delco or ngk's

 

Err..are you running cats? if so, possibly they don't enjoy an alky/water shower and melted as a result, causing excessive backpressure, etc... (O2 sensors will fail due to liquid water impingement, so should never spray except when eveything's hot.)

 

You suspect an exhaust blockage;
test exhaust back-pressure using an exhaust pressure gauge (temporarily screws into one of the O2 sensor bungs);
rev engine; if it reads more than 5 psi, then it's blocked;
repeat test for each bank.

 

Great idea thanks....

I modified an o2 sensor plug and installed a fitting, just don't have any low pressure gauges around the house will go to the store tomorrow and see what is available.

Thanks

 

Thanks Joecar...your idea paid off. @ idle I had 5 psi, @ 2500 I had 30 psi. In any case I pulled the midpipes down...you should see the crud that came out. check out this link for the pics: http://www.ls1gto.com/forums/showthread.php?t=52454

Now the question is.....What caused it???