Julian's '91 200 20vt

[88a5tq]

I further messed the settings today while logging. No stalling but it did dip as low and 326 RPM at one point using these settings:

v3.3_u009216-A-2015.09.13-19.04.49.vemscfg

(13.28 KiB) Downloaded 1047 times

The main issue I came across was my base map had the min DC set to zero which resulted in the idle oscillating severely I guess from going to the extreme ends of the DC spectrum. I seem to have improved this I think but I am still stumped on one facet of idle control. Do any of you know how to have the IAC control catch a quickly falling RPM (out of gear coming to a light around 3k rpm) with an AC compressor load? Its my biggest driveability issue right now having to do with idle and shifting, etc. Its as if, when the compressor kicks on and I am instantaneously shifting out a gear, the idle will fall like a rock and I can barely shift into the next gear in time in order to make the ride bearable. If I dont get to the gear fast enough, it feels like this boat of a car dropped anchor lol. Anybody know what I mean??

Could the setting Im looking for be the IAC close delay under PWM idle control settings? I noticed strange oscillations from messing with the idle integral limits and deadband settings. Is that the key? IAC alpha-n load maybe? TIA cuz Im stumped!

[88a5tq]

After getting some help from Marc, I gave it another shot but ended up deleting the IAC valve and today I'm going to adjust the bump stop of the throttle valve to reach an idle RPM I'm comfortable with. Now to figure out how to adjust the stopper without destroying the flathead slot. I sprayed it with brake clean and PB blaster last night. I'll look at it more today.

Also my steel geared distributor seems to be making a lot of noise on startup. It might even be leaking oil?

[themagellan]

I'd look at it if it's leaking oil, or somewhere near it. If you're still on the distributor i'm sure you'll see misfires if oil creeps into the cap/rotor.

[88a5tq]

Agreed. I'm good there tho as I have Marc's COP conversion. At some point I'll do the timing marks and have a look at the whole thing out

[88a5tq]

It's been a very productive last night and today's day. Shifter bushing, distributor inspection, P/S belt installed. Dizzy is quiet now and the rattle from the front of the car is gone (!?) Lol. Not sure what that was actually. Ordered a 4k spoiler from Steve and my new coolant valve/sensor combo from ECS. Early next week will be busy now as parts trickle in.

[88a5tq]

Okay since not many of you may have deleted your IAC valve on the 3b, I figured this would be interesting. I was getting a bit of a drop-off feeling in power up top and the inability to hit my target boost since removing it. I looked at my logs and saw my tps was only hitting 98 max. I adjusted it and it was a little better after seeing 99%. I decided to take like .001 off of the surface shown below and now I'm hitting 100% again.

This occurred after adjusting the throttle open slightly at rest to raise the idle with the IAC valve gone. It was apparently enough to make seeing 100% physically impossible so I had to get creative...

[loxxrider]

It shouldn't matter if it's not exaxtly 100%... You can just adjust it in VEMS anyway lol

[88a5tq]

Oh well. Today I managed to do the driver side motor mount at least. Lol part of me wanted to ask you about that tps thing first too, Chris.

[88a5tq]

Still seems quite odd with the power feeling off at 68 F vs 74. I can't place it but it seems to have started after deleting the isv.

Not sure if it's related (lambda looked fine) but my fuel lines started sweating where they clamp to the underneath of the car. Scheduled for replacement Thursday. Get tired of working on the car after doing nothing but for a whole weekend. I'll leave this to an. ASE mechanic Maybe some boost was making it through the icv at WOT since that thing is open at rest anyway?

The way I'd describe it is the power is gone from like 6k to redline. I would need to drive the car again to be more accurate with the rpm's though.

[loxxrider]

Logz

lol

That's probably going to be a hard one to diagnose though.

[88a5tq]

Hah I'll see if u can figure it out on my own and then I will escalate the situ.

It may be too soon to tell but I think my distributor was leaking all over the top of bellhousing.

[88a5tq]

hover at 5k RPM.vemslog

(17 KiB) Downloaded 1002 times

Pretty weird but in this log you will see the car literally hovers right around 5 rpm during the pull. wtf is what I was asking myself basically.

[loxxrider]

That's not good to see... was the car actually doing that? Verified by tach and ear?

[88a5tq]

I don't actually think it did that. What does that say to you at first glance? Only thing I can add is that after cleaning both bellhousing sensors, the lower bolt was sorta loose and upon reinstallation it stripped so I put a longer bolt in. I'm not sure if those sensors vibrating could cause that rpm issue.

EDIT
I cant believe the engine physically did that. The full log shows that as the only time the rpm error came up. I think all the times i tried to look at the gauges instead of the road during WOT, I was seeing the rpms flypast that mark. Sorry I cant be more helpful tonight. Long day and just dont feel like driving

Before anything else I'd like to take another log just to see what's what. If it persists, I'll go back to an icv lol

[loxxrider]

I wonder if your flywheel sensors are seeing that bolt and are not able to resolve the correct RPM because of it? Don't drive it much at WOT if it's doing that. You need a good RPM reference for the tune to do it's thing!

[88a5tq]

I got those sensors cranked down pretty good now. I'll do an observant test after work today. I freaking hope that's the problem. It's so boring at high rpm lol. Where the turbo and cams thrive, it's just a limp fish handshake (like the safelite installation guy :( ). His handshake made me think he was a 2-faced butt head/face. Two butt faces?

[88a5tq]

Still not ready to look any harder at this issue. I may have found a completely FULL catch can that had my entire car smelling of CC oil and shit while driving. I keep trying to figure how excess oil in the CC could cause my weird power issues. I mean I did settle the hovering rpm issue by getting 2 new bolts on those sensors but there might still be a low power scenario going on at WOT & high rpm. I reverted to my IAC tune and threw the valve back on. Strange getting used to driving with it on there in traffic.

Maybe ill change my plugs for kicks tomorrow and take a look under the hood again. I had a panic attack nearly when I started thinking maybe my clutch was slipping lol. I also will try venting the CC in case theres massive blowby or something crazy behind all this weirdness. Shit my birthday is the 27th and I hate when my cars are f#cked up for it lol

[88a5tq]

I just checked my catch can vac tube off the intake and I put my finger in it to plug it while revving the motor in neutral (of course lol). I got ZERO vacuum off of it. I need a better place to tap into besides right before the huge k&n.

What prompted me to test the vacuum was I cleaned the CC with brake cleaner and left it vented. Then when I saw steam coming from there with the hood closed I began to panic because I wasn't sure if it was exhaust or steam which was likely exaggerated by my hard pull right before that and using w/m all the time. When I put it back on the intake tap point I checked vac. IVE always suspected it wasn't doing shit there!

[DE80q]

Have you ever done a comp. test? That's a lot of blow by to fill that can.

[88a5tq]

I agree. I could swear I did the test on 3 separate occasions. I remember once when I bought the car (below zero out and no oil in cyls., all between 170 and 215 psi) and again before blowing the HG. I thought I'd done it again since the head came off but the last time the numbers were between 160 and 180 IIRC. Seemed "stellar" to me at the time

I don't think I want to know what the #s are right now hah. I haven't had anything bad happen since those tests besides the HG going out. I use great oil and it's never looked bad on the dipstick. I even started using a magnetic drain plug. Even talking about it being a problem is making me sick.

Isn't it true that the rings could stand to benefit from a higher vacuum on the crank? Better seal and such? I really need to get that worked out.

[88a5tq]

I replaced the coolant valve/sensor assembly behind the engine today. Also got new feed/drain fuel lines underneath of nylon construct. Had a shop do it next to us which we've been using to gas up our funeral vehicles since the 60's.

I know it's nothing new to be betrayed by a mechanic, but by one which you've been working with for that long?! Those idiots forgot I scout out all the work on my cars first and then decide much further down the line, once I decide not to tackle it, exactly what I want done by a professional.

Upon inspection by an ex-alcoholic mechanic there, they decided they wanted to drop the freakin gas tank to replace the lines. "Lol wtf" crossed my mind. They said they didn't want to tap in where I told them to because there were metal fittings ABOVE the tank, that were part of the fuel lines in question, that had started corroding just as bad. I then went over in person and looked at the top of the tank from the trunk only to see all plastic fittings with either rubber or more NYLON line and zero rust. I was pretty surprised they tried to turn a $150 job into $700, considering who we are to them and that we decide who we get gas from.

I'm over it hah. They did refuse to replace the breather line though. I can do it for like $15 myself. I was more concerned about the lines carrying actual liquid fuel. The car seemed to start much more quickly after that got finished.

[88a5tq]

This is how much oil was in the CC tonight after 2 days and heavy abuse in 1st through 3rd gears.

Typical 16.9 FL oz water bottle

14431379424161733480483.jpg (2.3 MiB) Viewed 24262 times

Things I've noticed:
First gear usually pulls quite hard all the way through.
Seems better when coolant temp is down to the 1/4 mark.
Low MAT seems to improve the issue.
Rpm's below 5k pull really well. Good power.
All low power symptoms occur above ~5500 rpm I believe and in 3rd gear IIRC.

Is this the rings? I will do a compression test on my birthday so results Sunday night.

ALSO, I don't notice smoke of any color under acceleration behind me and once in a while on a cold start the exhaust is slightly white as if the new effing valve stem seals are leaking. It goes away within 15 seconds of driving though.

[88a5tq]

Kind of sound like a broken valve spring for a minute until I topped up the oil and drove away.

Maybe it's valve float and that's what is causing the power loss. I have some research to do. I'd rather do valve springs with the engine together than a whole freaking rebuild!

[loxxrider]

Or it could be in the tune... I am in Budapest right now with no laptop charger so I can't really look at it, but make sure you don't have MAP retard on too much or something. I don't think you do as I recall, but it's worth checking everything like that in the tune.

[88a5tq]

Nice Budapest sounds fun
I will comb through the tune just in case. I had the same thought with ignition retard a couple days ago so I checked high rpm ignition angle and found everything was correct compared to its position in the table. I was really hoping to find something with the timing since it felt just like ign. retard. Last night I was leaving an icecream place and it did sound just like u had a single broken spring and that was with about a 1/4 qt low on the dip stick. I filled it with a half qt accidentally and drove a block without any driveability issues and it very suddenly went quiet. I feel like changing to Ti bits and 034 high springs before winter instead of rings. Next summer I'll do rings I think since the car runs great otherwise. Thanks Chris, enjoy your travels.