Fuel Cut

[Killtodie]

ok, today I'll replace the rest of ignition cables and see if they make a difference.

 

As far as rotor and cap, they are inexpensive, might as well replace them for good measure, any specific brands recommended?

 

 

well, i checked the timing, its 10, replaced all the ignition cables, that didnt fix it. rotor and cap look good, i took em out and cleaned all the contacts, no improvement.

 

I swapped the ignition cables one more time and looked over the spark plugs, they look new with a .043/.044 gap

 

The "raspberries" occur at 4.2k rpm, does not sound like it missfires at all anymore, just that weird thing. No idea what it is.

 

Will reducing my gap to .036 solve this issue or should this be taken to another direction?

Edited July 27, 2011 by Killtodie

[Indiana]

Cracks in manifolds or leaking manifold gaskets cause strange noises and since it seems like a repeating sound its more likey one of the exhaust ports leaking.

 

 

[Killtodie]

I recently replaced the manifold, there is no smoking from it. I checked on the tightness of some of the bolts that I could reach without removing stuff, all 3 of them, they felt fine. Well, one I tightened up some more. I reused my old gasket, sprayed it with copper on both sides.

 

working on the exhaust side is a pita, but if you think that's where my problem lies, I can take it all apart and retighten it as needed, get a new exhaust gasket and a turbo housing gasket. Wont cost me much.

 

 

There is a 24 hour autozone 20 minutes away, I cant sleep, they have both gaskets in stock. I guess I'll drive there and get them and tear this down. Cant sleep anyway, need to be up at 6am with the Quest, might as well get something done. I hope that this sends me on the right track.

 

 

Picked up the gaskets, time to take this apart. Felpro baby

Edited July 27, 2011 by Killtodie

[StarquestRescue]

Check the maniflod for flatness with a strait edge when it is off.

[Killtodie]

Check the maniflod for flatness with a strait edge when it is off.

 

 

i had it surfaced 2 months ago, i'll check gain now that itsw off

 

 

Update:

 

Replaced both gasket, tightened everything down, let it idle for 10 minutes to burn off all the copper spray. i'll wait another hour and take it for a drive, dont wanna wake the neighborhood.

 

Update #2:

 

So I drove the car. The first time I slammed the pedal, revved up to like 5.5k, no problem, seems like it fixed! Second time around the block, starts doing the same thing, did it once more but on the 4th time it didnt.

 

FSM says 11lb torque on the exhaust manifold bolts, I cant get a torque wrench there but I tightened them down plenty, at least 15lb. What the hell else could this be? It seemed to have been fixed at first when I did my first pull but then it started doing it again. So temperamental.

 

 

This is the mating surface for the turbo housing, its not smooth. I tried taking that to a wire brush but it didnt help. I have a new metal felpro gasket that I sprayed with copper and took those 4 bolts to 55lb. Could that possibly be a leak?

http://img685.imageshack.us/img685/5480/unledmnt.jpg

Edited July 27, 2011 by Killtodie

[Caliber308]

 

 

Will reducing my gap to .036 solve this issue or should this be taken to another direction?

 

You want the widest gap possible prior to flame out on above stock boosting levels. Try .039. Sometimes you have to experiment with the Spark Plug gap to get it right.

 

Bill

[Indiana]

There's your raspberry noise leak. When that heats up its leaking and if you are only using that single layer stock gasket they changed to multilayered later on, that will leak after everything is heated up. That's actually several layers of rust and if you had a blasting cabinet you could remove it all and find a decent surface. If the turbine housing is the same way it needs cleaned up too. Get off as much as you can and use the DSM/EVO multilayer gasket. You can't make a seal on there the way it is now. The DSM has a slightly larger opening so you can get rid of that ring if you haven't already. The torque for the manifold nuts is very little its barely enough to mash the gasket but it was that way on purpose because that was their fix for a poorly designed manifold that warped. If you had it surfaced and its flat tighten them down.

 

 

 

 

 

 

[Killtodie]

I might just take it back to the shop that surfaced it before, i dont know why i didnt have them do the turbo housing part.

 

 

Took the turbo housing off and tried hitting that surface with a chisel and hammer, nada. I'll take both back to the same shop that prepped it for me earlier and have them take some off the mating surface, they only charge $20.

Edited July 29, 2011 by Killtodie

[Killtodie]

Got my manifold and turbo housing done, I'll be installing it in later tonight, I think this will fix the problem, the engineer who worked on it said it had a bad leak.

 

 

http://img26.imageshack.us/img26/5396/img1013o.jpg

Before

http://img228.imageshack.us/img228/7286/img1063t.jpg

After

 

 

 

 

Edit:

 

This DID NOT fix my problem. I am PISSED! >.<

Edited August 5, 2011 by Killtodie

[Indiana]

With the wastegate actuator arm not connected to the pin of the lever for the flapper, put it up next to that pin and the arm needs to be about 1/8" too short to reach the pin to hook it on. Not 1/32" and not 1/4" just about 1/16"-1/8". It will take both hands to pull the arm out and get it on the pin. This puts enough load on the wastegate flapper to make boost. If the arm is too tight that can cause the boost to wait too long until it opens then it will open all of a sudden then try to slam shut and will give this flutter sound at the point right where it should be open but can't be then needs to be closed but closed too quick. It takes so much boost pressure to overcome the spring in the actuator but its to open smoothly and if you limit the range of movement that just means it will want to bounce just like what happens when you cut parts of the the springs off your struts and the car rides like total crap and your head jerks off. This is not how you make more boost and its a reason why its not told in the FSM how to adjust the tension on the actuator arm so people would leave it alone and to the ones that worked specifically on turbos. That tin plate on the turbine housing, there was one person that had that Ragdoll hack rebuild their turbo and that was leaking and they had issues like you described. Is that plate rusty and pushed out from the flange its supposed to seal? Are the bolts tight and not stripped that hold the cover plate on?

[Killtodie]

I was going to ask about that arm. Currently the hole is about 3mm away from the wastegate arm.

I'll post a pic in a bit so you can see how it is normally. Sorry, I dont do inch fractions, need a metric reference.

 

 

Here is a pic

http://img534.imageshack.us/img534/2358/img1081b.jpg

 

Is that good?

Edited August 5, 2011 by Killtodie

[Indiana]

If its 3mm away and you can put it on with one finger that must mean something is wrong or we aren't communicating. You can't pull the actuator arm out against that spring with one finger. 3mm should do it but first the flapper lever needs to be all the way back so the wastegate path is closed then the actuator needs to be too short to reach the pin to slide it on. Have you ever looked inside there to see if there's something stuck in the wastegate opening or if its cracked or someone ground it open larger and screwed it up? You pulling on the arm is not the same as when boost pressure acts against the spring. If you pull on that actuator arm, it takes some force to pull the arm out and when its mounted in the car you can't easily do that you need to use both hands to get the arm pulled out to hook it onto that pin.

 

http://www.b2600turbo.com/images/WGactuator.jpg

[Killtodie]

I edited my post Indiana, I meant I can use one hand to put it on. Its tough.

Nothing stuck in the wastegate, I inspected it earlier.

I got a two tiny exhaust leaks from the turbo housing to the downpipe, I reused that gasket too many times, need to clean the contacts on both. but that shouldnt cause the issue...

 

 

What I'm thinking of doing:

-clean the surface of the downpipe and turbo exhaust side, use new gasket

(in no particular order, probably from cheapest/easiest to hardest)

-borrow a working dizzy, swap it out

-install a wideband

-extend the fuel pressure gauge so I can see it while driving

-recheck all ignition wires, spark plugs.

-check for a boost leak

-check timing (for the 5th time)

-swap ignition box

-try to find a cheap fuel pump, I don't trust my current one.

 

The car can rev up to 6k RPM at idle no problem, just as soon as I start driving it, it starts to flutter.

Edited August 7, 2011 by Killtodie

[Killtodie]

I think I might have found the problem:

 

Today I swapped the dizzy, ignition box and ecu. none of which helped. Then I saw that my knock senor was bad, the smooth plastic was cracked off exposing the insides. This might be causing my problems, I dont have a spare so I will look for a new one.

 

Holy crap, a new one from Rockauto is $77!!!

Edited August 12, 2011 by Killtodie

[StarquestRescue]

I lost track of what the problem is. Is it the raspberries, the misfire, or back to the fuel cut.

 

Edit, oh i see it is a flutter now. What does a flutter sound like?

Edited August 12, 2011 by StarquestRescue

[Bag-O-Chips]

The flutter Toadie is mentioning sounds like a 2-step or even a No-lift to shift. It misfires rapidly at high RPM

[Technology]

If you want to test whether the knock sensor is causing this problem, unplug it. It's one of the beautifully simple things about trouble shooting these cars. Think something has a problem? unplug it.

 

knock sensor problems will feel like a drop in power, it won't cause strange noises. Fuel fut is like hitting a wall once, then boost comes back on. Your video sounds like a stutter. Jet valve head? Burned out jet valves cause strange running issues, and I suppose if they're bad enough prevent revving like that.

 

Also, rod knock will get worse the more you drive it. Do you feel like the trouble has remained the same since it began or gotten worse over time, and continues to get worse as you drive it? (also rod knock is audible while free-revving the engine in the driveway).

[Technology]

Also, get someone to drive behind you and sniff your exhaust while you do this. Or get a wideband. the first is cheaper, but only the first 30 times. Edited August 12, 2011 by Technology

[Killtodie]

Wideband is on the table of things to get.

 

I'll unplug the knock sensor and see how it feels without it.

 

The head is jet valve, I recently installed the deletes, new orings on them, everything was double checked for torque.

 

The problem has remained the same, I have not noticed it getting worse, only better when I replace things, like plugs and ignition wires.

 

What does rod knock sound like? me engine has some clanky noise to it but I was told its the mechanical lifters, Bag o Chips says it's clicking too much. That noise has been with it since I got the new engine installed just over a year ago.

[Hoosierquest]

A rod knock will generally get louder under load so if you power braked it a little it would be more pronounced.

[Indiana]

You can pull a plug wire off one at a time and listen for a change in the sound, the one that makes the difference is the one that's knocking if that's what's going on.

 

Who knows what a cracked ignitor causes, maybe nothing but maybe everything. Look for an 88/89 ignitor to swap in.

 

I don't remember what events happened, when you took out the jet valves out did you clean the lifters? You check compression? Say there's an exhaust valve that's not hardly opening from a lifter that's full of air or crap that prevents it from pumping up, that leaves much less time for the exhaust to blow out so that cylinder could get hotter and have the air/fuel igniting when it enters before ignition. This would get worse as rpms increase. If its on the intake side I don't think you'd know it would just be lean. If you didn't do anything to the lifters and didn't check compression then one of the lifters might be too pumped up and if an exhaust valve isn't seating, that will blow fuel out into the exhaust where it ignites and causes the symptoms you have and as rpms increased it would get worse.

[Killtodie]

When I removed the jet valves I did the adjustment for the mechanical rockers and rotated the crank by hand, everything was smooth.

 

Like I said, i swapped the ignition box for another one, 88/89, made no difference.

[StarquestRescue]

The flutter Toadie is mentioning sounds like a 2-step or even a No-lift to shift. It misfires rapidly at high RPM

That is almost certianly a rich misfire. With enought boost i have had the stock ignition missfire in the low 11's afr. A msd type ignition is a huge help, but it to will missfire if a guy shoves a enoght boost and fuel in to the engine. Any weak ignition part makes the problem worse. Wires cap rotor ect.

 

First he needs a wide band, than some thing to tune with. a maft or just a safc2 should work since he is probably not moving enough air with the 12a to completely screw up the aif flow signal. Once leaned out the misfire should go away. Like when he leaned it out with the e85, blend. I would not have recommended that, but it pretty much proved the point that the car is to rich under boost.

 

Perhaps an msd alone will cure the misfire, but that does not address the rich problem at its source.

 

Now the big mystery is why out of 10 cars with similar mods some will run fine and some will not. As the mod level increases the likelihood that a untuned stock ignition car will run right becomes less and less.

[StarquestRescue]

Now with a wide band you have to watch really close, because once a misfire starts the wide band will read richer from the unburned fuel in the exhaust. So you need to pay attention to what the afr was right before miss started. Easier said than done because the airflow is increasing rapidly and the afr can go from 14 teens to low 10's in a instant as the turbo starts to really move some air.

 

And like Indiana is saying a sick engine will never run right. It did sound like it was tapping up a storm. a leak down test can reveal problems a compression test can not. Chip, maybe you can help him with that. Any body with big power goals needs to have and know how to use this tool.

[Killtodie]

Why would a stock engine (no bolt on upgrades) have problems running? only upgrades I have is hardpiping and a 1gmas but running a stock mas made no difference.