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Knock problems continue

E

echostatic

Turbooo
seeing how i may have a bad alcohol pump, i turned the alky injection off, turned the boost down to 14lbs, and switched from the turbo tweak alky chip to the red armstrong 93 octane chip the car came with. if my boost is so low, i wouldnt think knock would be a problem anymore. im still getting it though. i made some 60mph freeway runs on the way to work this morning nad could pretty consistantly get knock. it was hard to be certain with all the other noise, but i think i could hear it very briefly under the hood. sometimes i would just get it for a moment when i went WOT, but sometimes it would continue to creep up. the highest i saw on the scanmaster was 4.9* retard from creeping up. what could cause a knocking problem, assuming gasoline is not an issue?
 
i played around some more at lunch, and i didnt get hardly any knock. under two degrees. i wasnt on the freeway at high speeds though.

the fuel pressure at WOT should be mid 40s. my fuel gauge is unfortunately under the hood. scanmaster recorded the o2 value of my freeway runs as over 800 though. injectors are not new, but the fuel pump is.

i have noticed a good deal of false knock during normal driving. i can cruise along at 40 on the street or 60 on the freeway and see the casper gauge randomly light up and the scanmaster sometimes agree with it showing several degrees of retard. theres also something rattling around underneath the car pretty bad while moving, but so far i havent found what it could be.
 
Now since you've lunched a headgasket already and not much has been done other than the repair itself,right? I'd take this knock more seriously.
14 lbs of boost is certainly within the safe range on premium fuel but I'd still put that TT chip back in and start tuning it. 800 on the big end is fat and all but if you think 40psi is correct at WOT and full boost your off. You should see 54-56 psi with 14lbs boost, assuming it's pushing that boost at the big end of your run.

Put that TT chip back in and start tuning with it. Pull some timing overall and maybe pull some fuel at the WOT setting.

But get back under that car and fix what is banging around. Re-hang the downpipe and crossover pipe, check the tailpipes and muffler. Check mounts,motor and tranny. If you have something banging around your attempts to tune out KR is just masturbation.

What's wrong with the alky pump? and how do you know it's bad?


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i cant put the TT chip back in right now since using an alky chip with a sober car isnt safe. im fairly sure the pump has issues based on how the system is acting. at WOT the activation light will illuminate red, then shift to green like it should, but i will knock a LOT and i have to back off. sitting at idle and holding the test button with the knob set to 8 should quickly kill the engine, but it runs very smoothly, no stumble at all like it would use to do in that situation.

i could get fair performance running at 19lbs boost and the knob set to 8, but it was still somewhat iffy and i normally run with it set at 4-5. so, it works somewhat, but the pump seems really weak. a duscussion with julio and the folks at turbobuick.com confirmed my pump suspicions. i need to pull it and send it to julio for testing. could just be debris.

i think that is why i destroyed the head gasket in the first place. it wasnt until very recently that i tried WOT passes again. maybe i was wrong about fuel pressure, i really dont have a way to see it except when idling with the hood open.

the 14lbs of boost and red armstrong chip is a temporary solution to allow me to keep driving it until this is worked out. i assure you i take this knock very seriously. its no laughing matter!
 
You know you can just pull 2-3 degrees off the 1/2 and 3/4 timing settings to get it back down to a non alky chip.That's not to say it'll be a regular pump gas chip but it will put you back into a tuneable chip and then you can tune out some more timing.

My alky pump sucked some plastic casting flash from the alky resevoir tank and wouldn't spray either, but that happened within 50 miles of installation.

I fixed it myself by tearing the head off the pump and cleaning out the bits of plastic. All under Julio's direction of course and saved myself some down time.
 
i pulled the pump tonight to send to julio, and i think i might have gotten very lucky with that rattle. i figured id take a quick look around while i was under there and the first thing i saw were the two pipes crossing in front of the radiator. theres an insulator where they cross over eachother to keep them from making contact and that insulator encircles 3/4ths of one of the little pipes. it was turned in suck a way that the open side was torward the other pipe, and they were making contact. i pulled them apart and released, and the sound they made sounded a lot like that rattle. i rotated the spacer so they didnt make contact anymore. i hope i got really lucky with that :)

ill be sending the pump to julio tomorrow.
 
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pump is sent, that insulator over the pipe crossing somehow fell off so i bought some tubing from autozone and some zip ties. put it on, and its still rattling. i noticed one of the pipes was loose and that could be the problem... so when i can im gonna try to get to the bolt and tighten it.
 
i know im getting a lot of false knock, but i think im getting real knock too. even with 93 octane, a rich mixture and 14lbs boost. i couldnt make an onramp or freeway pass without the knock gauge creeping up every time i went WOT.
 
ill have to keep an eye on the scanmaster next time... im nearing the limit of my multitasking now that ive got it, trying to watch it, boost gauge, knock gauge, and, if i can spare a glance, the road :)

the scanmaster updates so painfully slowly, i dont always want to keep on it while the casper gauge is showing knock. that remind me of another important question... the casper gauge will stay illuminated at the highest amount of knock detected for a few seconds. if you go WOT and downshift, resulting in brief transitional knock, but still enough to max out the casper gauge, how are you supposed to know if youre knocking for those few seconds its not giving you a current readout afterwards? you cant necessarily rely on the scanmaster, its updating less than once a second and a lot can go wrong in that time if you have real knock.
 
echostatic said:
the scanmaster updates so painfully slowly, i dont always want to keep on it while the casper gauge is showing knock.
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I'm making the assumption you have the caspers in a pillar pod? If so, train yourself to just keep it in your peripheral vision in realtion to what colors are lit. I don't even notice green L.E.D.s anymore. Right now the scanmaster is your friend.

that remind me of another important question... the casper gauge will stay illuminated at the highest amount of knock detected for a few seconds.
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Yes, and I'm not sure what msec or seconds it resets. Maybe a reset after 1.5 seconds, but I know it seems like an eternity.

if you go WOT and downshift, resulting in brief transitional knock, but still enough to max out the casper gauge, how are you supposed to know if youre knocking for those few seconds its not giving you a current readout afterwards?
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You don't and that's the problem with knock alert(s). It's just a slap in the face milliseconds before the ECM starts to react.

you cant necessarily rely on the scanmaster,its updating less than once a second and a lot can go wrong in that time if you have real knock.
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Yes... you can rely on it. It maybe slow at 2 refresh screens every 1.5 seconds (I think) compared to the TT 6.0 w/ WB but it's better at diagnosing knock than the caspers gauge.

What I'm saying is you know it's detonating, you don't need to be watching the light show anymore,watch the KR numbers and at what O2 values on the scanmaster as it happens at. Your boost is low and your fueling is 800+,right ? The scanmaster will record the highest KR when the engine is in PE mode(power enrichment) look at the scanmaster instructions and get familiar with that function. Also I would isolate when this happens. Above 45mph?, at the 4-3 downshift? under full boost 4th gear and no downshift? under hard launch? before the alky sprays? will it show KR in park when you stab the pedal a couple times?

Then decide if it's real or false or transitional or burst knock based on when it happens. Test again and again and see if the numbers just show up high or ascend like 2.0-2.9-4.6 etc. or is it 19.9 right off the bat.

There is something that I'm still studying up on and that's "rich knock". not a whole lot written about it but it appears that too rich will cause detonation too. My tune is fat at 800 at 18lbs boost and the leaner I make it the less KR I see on the 3-4 shift, so there must be something to it. I'm just to much of a pussy to go down to 770.:whistle:

Don't get discouraged you may be just chasing a fuel pressure problem or a banging tailpipe or loose motor mount.

Maybe for experimentation you should turn the boost down to 10lbs.The try a few runs.


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yeah the casper gauge is in a pillar pod. i guess i should start paying more attention to the scanmaster and just watch the casper in my peripheral.

ill try and isolate when it happens... i dont think ive ever seen the scanmaster show knock anywhere near the 19.9 area though.

the casper gauge was going nuts at times today... id be cruising along, and all of a sudden itd quickly light up to the red. what was really weird was that it wouldnt stay lit up for a couple seconds like it normally does, but it would cycle to red quickly, then immediately cycle from green to red again. i didnt think it could do that.

ive also noticed that when accelerating normally, no boost, sometimes the casper gauge will show knock just before the tranny upshifts, usually into the red lights. the scan master will then give a readout of 1-2 deg. knock. it started doing this after i put the red armstrong chip in, so it might be tied into that somehow... i get my alcohol pump back later this week, so i should be able to install that again soon.

i can try some low boost runs tomorrow, see what happens.

the rattle from under the car has been cured, by the way. loose bolt.
 
Believe me, there's nothing like chasing a knock problem to shorten the learning curve on these cars.

You may have a caspers gauge problem too, either in an internittent power loss or just a bad gauge. I also bet you've still got a false knock problem under the car somewhere still or maybe a bad belt tensioner whacking the A/C compressor.
 
im not really seeing how intermittent power loss could cause that problem. i hope its not a bad gauge... my fuel pessure gauge just went out too. or at least i hope it did. its pegged...
 
something went terribly wrong this morning.

i turned the boost down to 10lbs and made some runs on the way to work.

first i made a couple 40 punches up to about 80 or so. there was a little knock right when i floored it, but it cleared up and stayed clear.

then i made a 0-90 punch when i got to a freeway onramp. thats when everything went bad. the first KR number to immediately flash up on the scanmaster was something like 36.0. i never heard any knock under the hood so i figured that had to be false. i stayed in it, keeping an eye on the scanmaster. i was getting all sorts of numbers the whole way through. 1.4, 0, .5, 3.4, etc. when i let off at 90 the engine sounded bad. i took it easy for the few minutes it took to get to work and popped the hood. there was a pretty loud ticking coming from the engine. not like it sounded when i blew a head gasket or anything, but i dont have much experience with weird engine noises so im not sure how to describe it.

i called up jack at JL enterprises and asked him about it. im going to replace the oil filter with a new one, and if it still ticks, he wants me to give him the old one to cut open and check for metal.

i have a strong feeling this will end with an engine rebuild.
 
I was going to ask the general well being of your engine beforehand, like does it tick,have good oil pressure,etc. I had a couple of wiped lobes and that contributed to my fight against the demon knock.

Reads like your going to go back to the begining and assess the engines health. And that means a compression test and maybe a leakdown test.

If this is something you can't do, I'd pay some shop to do it. You need to know what you've got to work with before we go any further.

The ticking maybe a header leak and the poor running issue maybe a fueling issue as well. So don't get discouraged just yet.

And file for your tax return as soon as possible.:poke::whistle:

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i found $300 in a bank i had as a child thats been sitting in my closet for years monday, so that helps with the cash thing a little bit :)

i got the car leakdown and compression tested in june, and it was all normal. i guess it couldnt hurt to do it again.

i called jack at JL enterprises today and told him about this morning. he thinks what may have happened, is when i blew the head gasket, head gasket material got down into the oil pan. and maybe the shop that replaced the gaskets didnt drop the pan and check. he wanted me to replace my oil filter and give him the old one to cut open and check for metal fragments, so thats what i did. im going to give it to him tomorrow.

if this turns into an engine rebuild, im going to do it right and get some strong internals. ive got a built rear end and transmission, a built engine would complete it. bit pricey though...

i dropped the TTA off with jack on monday for a 1000 mile transmission checkup he offers for free on transmissions he installs. i picked it up toesday and had him listen to the ticking. he said it sounded like excess lash on the lifters.

its interesting you should mention a fueling issue. i dont know if i have a bad gauge or what but my fuel pressure gauge is pegged with the car off... that aint right.
 
Looks like you'll be buying at least a new FP gauge and maybe a regulator too.

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oil filter was full of gasket material. im about to head over to kwikcar and chew them out, and see what they will do about this. i knew i shouldntve had them replace the head gaskets. bad bad call... kicking myself for it.
 
i picked it up toesday and had him listen to the ticking. he said it sounded like excess lash on the lifters.
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I had this too...and I came to the same conclusions as your mechanic. But I knew deep down I had cam problems,especially after adjusting(or retorquing) the lash and finding some metal in 2 back to back filter changes. I had wiped #4 and started wiping 2 other lobes.
 
my problems have apparently been caused by the torque converter ballooning and burning up the thrust bearing, the same reason my dads GN is getting a rebuild. unfortunately moneys getting a bit tight so im going to hopefully save ~50% by pulling the engine at home and bringing it in, then have him disassemble it, repair the damage, build the short block, then ill go pick it up and do the rest at home.
 
You can do the bottom end on your own if your mechanically inclined and meticulously clean. I did mine just for the helluva it when I put the cam and lifters in. Just get the crank turned/polished by a competent shop and buy your bearings from full throttle in the size you'll need. There's tons of useful info on setting the the thrust bearing over at TB.com and it's just a matter of torquing the caps correctly(which is laid out in the supplement manual).
If I can do it then you can. And I've spun my motor up to 5800 many times since then and I have 80PSI cold and 60 hot.

I don't have the total but I bet I don't have $250 in bearings and gaskets to do the mains and rods.

Was the convertor the stock one?


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