home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > maintenance & nonperformance

Reply
 
Thread Tools Display Modes
Old 12-07-2017, 12:16 PM   #1
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default Vehicle speed correlating to idle speed

Ah, weird title. Sorry. 1993 245 m47 lh2.4

Pretty much stage 0. This isn’t a huge deal, but I’ve noticed that every 240 I’ve ever owned doesn’t really idle above 1,000 even on cold starts. My old Toyota’s would shoot up to 1,500+.

Anyway, on my wagon on really cold days if i accelerate, the rpms will shoot up to 1,500 or so whether I’m in first gear idling or not. But the EXACT SECOND the car stops, rpms drop to normal warmup rpms. So essentially, it seems like this car kicks up the idle when the car is moving forward, but kicks it down at a stop. It does not have a cold start injector and this is the only 240 I’ve ever seen do this. It almost seems like it’s hunting a bit.

Any clues?
__________________
Current
-93' 244 m47-iPd sways, 13c, iPd cam, 2.5”
straight pipe
-93' 245 m47-iPd sways, T-cam
Past
-80' 242gt m46-
-88' 245 m47-Welded diff, gutted, 13g

Quote:
Originally Posted by Jack View Post
spill it MClovin and WTF happens to your glasses you piece of ****..
Feedback Thread
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 03:30 PM   #2
EivlEvo
Board Member
 
Join Date: Sep 2012
Default

No, but if it makes you feel better I SWEAR that my 240 idle chases the rhythm of my LEFT turn signal. Like when only the left signal is on, the motor goes up and down a couple of RPM with the cadence of the clicker.

Get out the foil hats!
EivlEvo is offline   Reply With Quote
Old 12-07-2017, 03:32 PM   #3
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by EivlEvo View Post
No, but if it makes you feel better I SWEAR that my 240 idle chases the rhythm of my LEFT turn signal. Like when only the left signal is on, the motor goes up and down a couple of RPM with the cadence of the clicker.

Get out the foil hats!
That could actually make sense. Maybe a voltage drop issue? Or something being tapped in to that shouldn’t be tapped in to? Idk
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 04:15 PM   #4
Fa182
Board Member
 
Join Date: Apr 2016
Location: Austria
Default

Not of particular help here but my 940 does this too.
When I'm slowly rolling to a traffic light, even in neutral, the rpms are around 1.300 or so, as long as I'm moving. When I come to a full stop, the rpms immediately drop to the usual idle below 1.000. I've always wondered about it myself and thought it's a bit weird, but didn't really care about it. I just thought it's normal.
My 240 did this as well.
__________________
- 945 Turbo, 1997.
- 245, 1993. Sold.
Fa182 is offline   Reply With Quote
Old 12-07-2017, 04:37 PM   #5
Cwazywazy
Board Member
 
Cwazywazy's Avatar
 
Join Date: Aug 2016
Location: Granby CT
Default

Is it possible that there's some wiring weirdness between the speedo/ecu? My 240 idles at about 700 regardless of temperature or speed.
Cwazywazy is offline   Reply With Quote
Old 12-07-2017, 05:03 PM   #6
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by Cwazywazy View Post
Is it possible that there's some wiring weirdness between the speedo/ecu? My 240 idles at about 700 regardless of temperature or speed.
No idea. My other 240 idles 700-800 regardless as well. But this car also has an intermittent odometer even though i replaced the gear and cleaned everything. It seems to only work after driving on the highway for a bit, or if i pull the cluster and shove the connector into the back of the speedo. Weird thing is, i know it’s a tight connection on the back of the speedo because i bent the little fingers inwards to grip the speedo. So it’s like it’s tight enough, but not deep enough? Difficult to explain.
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 06:38 PM   #7
dl242gt
Can play the blues
 
dl242gt's Avatar
 
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.
Default

I've noticed lh2.4 do this. Not really anything that seems wrong to me. The idle regulation is tied to vehicle speed. So it would seem proper that the engine idle could wander a bit especially with a cold engine and the vehicle is for example rolling along at five mph.
__________________
Dave,
1982 242 turbo. MVP coilover front and rear adjustable suspension. Bilstein HD. IPD 25/25 bars. 3" rusty MVP exhaust. Cosworth Sierra hot side T3 .48 with upgraded stock .42 compressor. Ported 90+. D&F Performance flowed 405 with enem V15 turbo cam, Clanky worn True Track diff. Flat hood 1979 242 front.

1993 245 Classic, 411k miles, enem V15. 5spd. IPD bars and chassis braces. New Simons sport exhaust from Scandix.
dl242gt is offline   Reply With Quote
Old 12-07-2017, 06:48 PM   #8
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by dl242gt View Post
I've noticed lh2.4 do this. Not really anything that seems wrong to me. The idle regulation is tied to vehicle speed. So it would seem proper that the engine idle could wander a bit especially with a cold engine and the vehicle is for example rolling along at five mph.
It’s just weird because it’s the only 240 I’ve seen this happen on. And it’ll stay at 1500rpm from 5 mph rolling speed all the way down to .5 mph or so, so it’s definitely not *correct*. Oh well guess I’ll ignore it.
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 07:21 PM   #9
dl242gt
Can play the blues
 
dl242gt's Avatar
 
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.
Default

I have had two LH2.4 240s and they both did/do this but it is with a cold engine in my experience. Once you've been driving and the engine is fully warm I don't notice it. One was an 89 244 that had a 561 ecu. I don't remember the ezk. My present 93 wagon does this with a 951 fuel and 169 ezk. Actually, I just put a chipped 146 ezk in there now. Runs great.
dl242gt is offline   Reply With Quote
Old 12-07-2017, 07:43 PM   #10
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by dl242gt View Post
I have had two LH2.4 240s and they both did/do this but it is with a cold engine in my experience. Once you've been driving and the engine is fully warm I don't notice it. One was an 89 244 that had a 561 ecu. I don't remember the ezk. My present 93 wagon does this with a 951 fuel and 169 ezk. Actually, I just put a chipped 146 ezk in there now. Runs great.
So it doesn’t do it with the chipped ezk or it still does? Cold electronics/engines are kinda just weird IME.
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 08:14 PM   #11
dl242gt
Can play the blues
 
dl242gt's Avatar
 
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.
Default

You know with the distraction of a heavy pedal enjoying the new found power with what little I drive. I haven't thought to look for that weirdness. I'm hardly driving as much as I used to and not on cold mornings for many months now. That's when I used to notice that weird idle stuff.
dl242gt is offline   Reply With Quote
Old 12-07-2017, 09:16 PM   #12
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by dl242gt View Post
You know with the distraction of a heavy pedal enjoying the new found power with what little I drive. I haven't thought to look for that weirdness. I'm hardly driving as much as I used to and not on cold mornings for many months now. That's when I used to notice that weird idle stuff.
Hm so you installed a chipped ezk on an otherwise stock na 240 and had good results? I may have to try that to get my mind off of the weird idling stuff.
PromiseRing is online now   Reply With Quote
Old 12-07-2017, 09:25 PM   #13
dl242gt
Can play the blues
 
dl242gt's Avatar
 
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.
Default

Well I have had an enem V15 n/a cam in there for about five years. Didn't know how poorly setup the stock timing curve was for my cam. But the chipped ezk is only a month ago and it completely made the car run and drive like it should have from Volvo. Power and torque at all rpms. Heavy flywheel not an issue. I'm sure an A or B cam in there would be similar. It added so much from about 3k rpms and up it's wonderful.
dl242gt is offline   Reply With Quote
Old 12-07-2017, 10:38 PM   #14
gsellstr
Vintage anti-ricer
 
gsellstr's Avatar
 
Join Date: Oct 2004
Location: Somewhere in a northern California smog bank
Default

That's related to 2.4. 2.4 will close the idle motor once the vehicle is stationary, leaves it partially open on decel once it's out of fuel cut mode. With it staying that high, I'd suspect the minimum airflow isn't set correctly. Make sure the throttle cable is set correctly, linkage from the spool to the throttle plate is set correctly, and the throttle stop screw should be set to 1/4 turn after it contacts the lever, so set the minimum airflow, assuming a stock-ish setup. That can actually play a pretty big difference.

I've been dealing with idle issues a lot lately since I tweaked cam timing a bit.
__________________
RIP
Doug Williams aka Mr. Doug 4/15/2009
Pete Fluitman aka fivehundred 7/14/2013
Mick Starkey aka TrickMick 1/10/14

74 144 B20
http://forums.turbobricks.com/showthread.php?t=224983

90 745Ti
http://forums.turbobricks.com/showthread.php?t=334698

If you need Superpro bushings PM me for price and availability!
gsellstr is offline   Reply With Quote
Old 12-08-2017, 10:27 AM   #15
PromiseRing
We don't even like Volvos
 
Join Date: Feb 2014
Location: Missouri
Default

Quote:
Originally Posted by dl242gt View Post
Well I have had an enem V15 n/a cam in there for about five years. Didn't know how poorly setup the stock timing curve was for my cam. But the chipped ezk is only a month ago and it completely made the car run and drive like it should have from Volvo. Power and torque at all rpms. Heavy flywheel not an issue. I'm sure an A or B cam in there would be similar. It added so much from about 3k rpms and up it's wonderful.
Good, because i just ordered 2 B cams! Maybe a chipped ezk will be on the fhrusymas list if it makes it that much more driveable.
Quote:
Originally Posted by gsellstr View Post
That's related to 2.4. 2.4 will close the idle motor once the vehicle is stationary, leaves it partially open on decel once it's out of fuel cut mode. With it staying that high, I'd suspect the minimum airflow isn't set correctly. Make sure the throttle cable is set correctly, linkage from the spool to the throttle plate is set correctly, and the throttle stop screw should be set to 1/4 turn after it contacts the lever, so set the minimum airflow, assuming a stock-ish setup. That can actually play a pretty big difference.

I've been dealing with idle issues a lot lately since I tweaked cam timing a bit.
Ah so idle motor is open when moving (even in neutral coasting)? Weird. I remember adjust the tps on this car to click at the slightest throttle movement, as well as taking up any slack in the cable. I have also cleaned/swapped IAC valves before. I will check the other things as well.
PromiseRing is online now   Reply With Quote
Old 12-08-2017, 12:39 PM   #16
emem1160
Board Member
 
Join Date: Dec 2016
Default

I think the take home message here is that the Idle Air Control valve (Essentially it is a choke... ), really is causing high RPM problems with our old volvos: most noticeable when we come to a stop but also when we start the cars when it is cold out. This issue may or may not be related to the throttle linkage but more than likely is a LH2.4 fuel injection problem/limitation I am learning

( I have noticed on my 89 244 with a 940t ECU that when I cold start the car (10-20degrees), I am at 2000-2500RPM before the car warms up, this problem was not there before I did a +T, also have the "coming to a stop RPM problem" you describe... )
emem1160 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 12:21 PM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.