Car won't drop to low idle after Engine Swap.
04-16-2004, 09:37 AM
#1
Donating Maxima.org Member
Thread Starter
Join Date: Mar 2002
Posts: 797
Car won't drop to low idle after Engine Swap.
After getting my JDM engine in last weekend I have a couple little quirks.
Most irritating is that the engine will only idle at 1500RPM. The set screw on the IACV is closed all the way, and the throttle cable isn't obstructed anywhere.
For the first couple hours the ECU was throwing a code 13 (Coolant Temp Sensor) and I'm wondering if the sensor's still bad even though the code went away. Maybe the ECU's thinking the car's still cold and holding the idle up?
Thoughts, other ideas?
Most irritating is that the engine will only idle at 1500RPM. The set screw on the IACV is closed all the way, and the throttle cable isn't obstructed anywhere.
For the first couple hours the ECU was throwing a code 13 (Coolant Temp Sensor) and I'm wondering if the sensor's still bad even though the code went away. Maybe the ECU's thinking the car's still cold and holding the idle up?
Thoughts, other ideas?
04-16-2004, 09:56 AM
#2
Check to see that the IACV solenoid has the little spring behind its black piston.
Another thing, but a little stupid, make sure the throttle cable length is set correctly (I know, but anyway).
Re-check all vacuum hoses, and connectors.
Another thing, but a little stupid, make sure the throttle cable length is set correctly (I know, but anyway).
Re-check all vacuum hoses, and connectors.
04-16-2004, 09:58 AM
#3
Maybe it's stuck. Or there might be a vacuum leak somewhere. You could try:
1) Take the red temp sensor out and a) replace it with your old one b) clean it and reinstall
2) Take out the iacv and clean it. The valve gets stuck. Considering how bad the TB was, I wouldn't be suprised this wasn't stuck too. Or you can install your old one.
BTW. How did the Y fit on this new engine??
1) Take the red temp sensor out and a) replace it with your old one b) clean it and reinstall
2) Take out the iacv and clean it. The valve gets stuck. Considering how bad the TB was, I wouldn't be suprised this wasn't stuck too. Or you can install your old one.
BTW. How did the Y fit on this new engine??
04-16-2004, 10:21 AM
#4
Donating Maxima.org Member
Thread Starter
Join Date: Mar 2002
Posts: 797
I might try to take the coolant sensor out today. Is that area under any pressure/gravity feed? (ie would it spurt coolant if I take it off or is it high enough up)
The IACV is off my old engine. The JDM was literally filled with corrosion and weird stuff. I think I may have ripped the flat part of the gasket when I was putting it back on, so I'll order a new one of those when I get a chance.
The spring is in the piston for the IACV valve, I made sure of it when I put it together.
Jeff: You gonna make it to the spring fling tomorrow? I'm trying to get up there, hopefully my car won't fall apart on the way up
Hehe, remember how the Y was too long last time? Yeah. It was too short this time. lol. It was a lot closer though, so we just pried it in with a big breaker bar. It seals way better in the rear. Without the axles in I was able to get a wrench on that last nut and really cinch it down.
My cat's gone now though
We were screwing around while I still had my spare engine. Put donut spares on the car and drove around to the ricer meets. I nailed the cat on a driveway lip so a bunch of chunks fell out of it 
The IACV is off my old engine. The JDM was literally filled with corrosion and weird stuff. I think I may have ripped the flat part of the gasket when I was putting it back on, so I'll order a new one of those when I get a chance.
The spring is in the piston for the IACV valve, I made sure of it when I put it together.
Jeff: You gonna make it to the spring fling tomorrow? I'm trying to get up there, hopefully my car won't fall apart on the way up
Hehe, remember how the Y was too long last time? Yeah. It was too short this time. lol. It was a lot closer though, so we just pried it in with a big breaker bar. It seals way better in the rear. Without the axles in I was able to get a wrench on that last nut and really cinch it down.
My cat's gone now though
We were screwing around while I still had my spare engine. Put donut spares on the car and drove around to the ricer meets. I nailed the cat on a driveway lip so a bunch of chunks fell out of it
04-16-2004, 10:48 AM
#6
If the car is cold, there shouldn't be any pressure. It's fairly high. Unscrew the 10mm coolant bleed bolt that's right next to it. If no coolant comes outa there, it shouldn't when you take off the sensor.
Gasket. You can cheat on the gasket if you use some gasket sealer on/around the crack. Hell, put a small thin layer on both sides.
Yeah, I'll be at the meet tomorrow. heh
Y LOL!! Figures! You need another cat? I have another stock one I can just let you have. I can't use that size anymore anyway. My exhaust is too far modified (ie.. dimensions etc) for any of the stock stuff to fit anymore.
Gasket. You can cheat on the gasket if you use some gasket sealer on/around the crack. Hell, put a small thin layer on both sides.
Yeah, I'll be at the meet tomorrow. heh
Y LOL!! Figures! You need another cat? I have another stock one I can just let you have. I can't use that size anymore anyway. My exhaust is too far modified (ie.. dimensions etc) for any of the stock stuff to fit anymore.
Originally Posted by Spipedong90
I might try to take the coolant sensor out today. Is that area under any pressure/gravity feed? (ie would it spurt coolant if I take it off or is it high enough up)
The IACV is off my old engine. The JDM was literally filled with corrosion and weird stuff. I think I may have ripped the flat part of the gasket when I was putting it back on, so I'll order a new one of those when I get a chance.
The spring is in the piston for the IACV valve, I made sure of it when I put it together.
Jeff: You gonna make it to the spring fling tomorrow? I'm trying to get up there, hopefully my car won't fall apart on the way up
Hehe, remember how the Y was too long last time? Yeah. It was too short this time. lol. It was a lot closer though, so we just pried it in with a big breaker bar. It seals way better in the rear. Without the axles in I was able to get a wrench on that last nut and really cinch it down.
My cat's gone now though We were screwing around while I still had my spare engine. Put donut spares on the car and drove around to the ricer meets. I nailed the cat on a driveway lip so a bunch of chunks fell out of it
The IACV is off my old engine. The JDM was literally filled with corrosion and weird stuff. I think I may have ripped the flat part of the gasket when I was putting it back on, so I'll order a new one of those when I get a chance.
The spring is in the piston for the IACV valve, I made sure of it when I put it together.
Jeff: You gonna make it to the spring fling tomorrow? I'm trying to get up there, hopefully my car won't fall apart on the way up
Hehe, remember how the Y was too long last time? Yeah. It was too short this time. lol. It was a lot closer though, so we just pried it in with a big breaker bar. It seals way better in the rear. Without the axles in I was able to get a wrench on that last nut and really cinch it down.
My cat's gone now though
We were screwing around while I still had my spare engine. Put donut spares on the car and drove around to the ricer meets. I nailed the cat on a driveway lip so a bunch of chunks fell out of it 
and push started the car a whole bunch
04-16-2004, 12:11 PM
#8
keelan, have you tried forcing it to idle?
When I first got my car to a drivable state, I had grounded the VTC's. Since my old VE never clacked once in its life I had never done it before (so I didn't know that the ground was causing my ****ty idle and for some reason making it idle higher).
IIRC, mine even idled at 1300ish for a while there. I took it to a parking lot and just rolled it around in first gear, I would use the brake to pull the idle down. It helped abit, but it still didnt fix the crappy idle, which now I know was caused by the VTC ground.
Also when I was trying to get my idle set right I thought the IACV may have been bad, so I swapped it out with my spare (from an auto engine) and didn't bother setting it. Well nothing changed so I didn't swap my old one back, so my car has an Auto IACV and all (set for an auto) but it still idle's like a 5spd.
edit: oh yeah, now my car idles at ~600, and with the VTC's grounded it will normally idle at 600, but sometimes do alittle wave upto 800.
When I first got my car to a drivable state, I had grounded the VTC's. Since my old VE never clacked once in its life I had never done it before (so I didn't know that the ground was causing my ****ty idle and for some reason making it idle higher).
IIRC, mine even idled at 1300ish for a while there. I took it to a parking lot and just rolled it around in first gear, I would use the brake to pull the idle down. It helped abit, but it still didnt fix the crappy idle, which now I know was caused by the VTC ground.
Also when I was trying to get my idle set right I thought the IACV may have been bad, so I swapped it out with my spare (from an auto engine) and didn't bother setting it. Well nothing changed so I didn't swap my old one back, so my car has an Auto IACV and all (set for an auto) but it still idle's like a 5spd.
edit: oh yeah, now my car idles at ~600, and with the VTC's grounded it will normally idle at 600, but sometimes do alittle wave upto 800.
04-16-2004, 02:55 PM
#10
Senior Member
Join Date: Aug 2000
Posts: 2,807
The reason why it idles high is the JDM coolant temp sensor has a different calibration than USDM. for example you know the small connector that operates the temp gauge in the dash. Mine still has the JDM sensor and it doesn't move to the middle until coolant is 210*F+, it stays below C until 190*F and from C to half distance is 190-210*F. Install a new coolant sensor that should fix the cold idle issue.
04-16-2004, 03:03 PM
#11
Donating Maxima.org Member
Thread Starter
Join Date: Mar 2002
Posts: 797
lol fun stuff.
Jeff: I used some RTV Sealant on the crack. And a test pipe would fix that cat problem right up.
Shawn: If you could bring the timing light, that'd be great. I've finally got 6 good coils too!
When I get home I'll check ye olde FSM for how to set base idle. I think you unplug the TPS and race the engine a couple times and then use the IACV screw.... I'll try that.
As far as calibration, the temp gauge is right, but I think the ECU sensor and the gauge sender are seperate.
Jeff: I used some RTV Sealant on the crack. And a test pipe would fix that cat problem right up.
Shawn: If you could bring the timing light, that'd be great. I've finally got 6 good coils too!
When I get home I'll check ye olde FSM for how to set base idle. I think you unplug the TPS and race the engine a couple times and then use the IACV screw.... I'll try that.
As far as calibration, the temp gauge is right, but I think the ECU sensor and the gauge sender are seperate.
04-16-2004, 04:02 PM
#13
Donating Maxima.org Member
Thread Starter
Join Date: Mar 2002
Posts: 797
Okay, still going to change the sensor, but I found a vacuum leak. The hose to the FPR was brittle and fell off. Replaced it, and the idle dropped about 300. I can still hear a leak back in the vacuum cluster**** area. When I get some more time I'll inspect further and replace the sensor.
04-16-2004, 06:15 PM
#14
Originally Posted by D-sta
Well maybe the TPS could be stuck on open or closed and when that happens it idles high. I forgot the procedure to reverse the status.
oops sorry I mean D-sta. If all the basic (vacuum leak, throttle linkage, etc) is all addressed and look into my beat your TPS is not adjusted correctly. Try moving the TPS when it's at operating temp and see if the idle drops, if it does effect the idle break out the FSM, ohm meter and adjust the TPS correctly. I can't remember which terminal to measure the ohm reading but it should be .900-1000 ohm at close throttle and 9-10K at WOTMIKE
04-17-2004, 10:47 AM
#15
Senior Member
Join Date: Jan 2001
Posts: 2,105
Originally Posted by Spipedong90
After getting my JDM engine in last weekend I have a couple little quirks.
Most irritating is that the engine will only idle at 1500RPM. The set screw on the IACV is closed all the way, and the throttle cable isn't obstructed anywhere.
For the first couple hours the ECU was throwing a code 13 (Coolant Temp Sensor) and I'm wondering if the sensor's still bad even though the code went away. Maybe the ECU's thinking the car's still cold and holding the idle up?
Thoughts, other ideas?
Most irritating is that the engine will only idle at 1500RPM. The set screw on the IACV is closed all the way, and the throttle cable isn't obstructed anywhere.
For the first couple hours the ECU was throwing a code 13 (Coolant Temp Sensor) and I'm wondering if the sensor's still bad even though the code went away. Maybe the ECU's thinking the car's still cold and holding the idle up?
Thoughts, other ideas?
04-17-2004, 11:05 AM
#16
Senior Member
Join Date: Jul 2002
Location: Bellevue, WA
Posts: 702
Won't drop to low idle
I had a similar problem after I drained the coolant out of the idle air control. I cured it by opening the coolant air vent bolt (while the heater control was set to full hot) atop the engine, in front of the throttle body, by the coolant temp sensor. Seems an air bubble gets caught there that leaves the coolant temp sensor high and dry out of the coolant.
When I vented the air, whump, the idle ran properly.
When I vented the air, whump, the idle ran properly.
04-17-2004, 02:44 PM
#17
Keelan, I couldn't find the damn parking lot for the meet, if you get this in time and want to swing by my house its fine by me
Also I was wrong, my car now idles perfectly with the VTC's grounded or not. The only exception is when I first hit the switch it jumps alittle to compensate, but after 5 seconds or so (on a warm engine) it goes back to 600
Also I was wrong, my car now idles perfectly with the VTC's grounded or not. The only exception is when I first hit the switch it jumps alittle to compensate, but after 5 seconds or so (on a warm engine) it goes back to 600
04-17-2004, 04:43 PM
#18
We got his timing confirmed. Geez Shawn. You've never been at the Southcenter meet?? Right across from Wendys.
350z on 19" volks was bad arsed. Turbo Miata showed up. Nice guy. Standalone LINK system. SS steel downpipe/3" exhaust. All tig welded. Work of art!
350z on 19" volks was bad arsed. Turbo Miata showed up. Nice guy. Standalone LINK system. SS steel downpipe/3" exhaust. All tig welded. Work of art!
04-17-2004, 05:13 PM
#19
Jeffy, I'm pulling the 8gauge wire from my dads car soon (replacing it with 4 gauge), can we meet up and make my kit sometime?
I've been to the lot once before, about 2 years ago, but my Dad was driving lol.
I've been to the lot once before, about 2 years ago, but my Dad was driving lol.
04-19-2004, 01:53 PM
#20
Originally Posted by MrGone
Jeffy, I'm pulling the 8gauge wire from my dads car soon (replacing it with 4 gauge), can we meet up and make my kit sometime?
I've been to the lot once before, about 2 years ago, but my Dad was driving lol.
Keelan. You get the idle fixed? Hell did you ever get the master cylinder replaced?
My engine also idles a bit high at around 900 or so but it's no biggie. That coolant suggestion is interesting.
04-19-2004, 02:13 PM
#21
Donating Maxima.org Member
Thread Starter
Join Date: Mar 2002
Posts: 797
Okay, so. Car still idles high, but thats low on my list. Turns out that noise I assumed was the PS pump was more accurately the alternator which started crapping out around salem.
The brake and battery lights came on intermittently, and I kept revving the car up and it'd go away. I assumed it was the new belt stretching, but it became more often and finally stayed on permanently about 15 miles out of eugene. I made it home and put the car on the battery charger. So now I'm limited to short trips in between battery charges. Autozone/Shucks/Knechte all wanted like $250 +$70 core for a reman no-name alternator, which they didn't even have in stock.
Got to work today and the ESP distributors have a bosch reman with 1 year warranty for $97 and it'll be here tomorrow. Damn POS car.
Oh, and the Master Cylinder: I got it replaced the day it came. Bled all calipers twice. I can lock up the wheels now, but it requires a few hard stops first. After that, it'll grab hard and lock the wheels.
I usually just stomp it a few times when I first get in the car and that gets 'em started. hehehe
The brake and battery lights came on intermittently, and I kept revving the car up and it'd go away. I assumed it was the new belt stretching, but it became more often and finally stayed on permanently about 15 miles out of eugene. I made it home and put the car on the battery charger. So now I'm limited to short trips in between battery charges. Autozone/Shucks/Knechte all wanted like $250 +$70 core for a reman no-name alternator, which they didn't even have in stock.
Got to work today and the ESP distributors have a bosch reman with 1 year warranty for $97 and it'll be here tomorrow. Damn POS car.
Oh, and the Master Cylinder: I got it replaced the day it came. Bled all calipers twice. I can lock up the wheels now, but it requires a few hard stops first. After that, it'll grab hard and lock the wheels.
I usually just stomp it a few times when I first get in the car and that gets 'em started. hehehe
Thread
Thread Starter
Forum
Replies
Last Post
Lakersallday24
6th Generation Maxima (2004-2008)
10
06-16-2019 01:35 AM
kjlouis
4th Generation Maxima (1995-1999)
11
11-24-2018 06:09 AM
laparka66
7th Generation Maxima (2009-2015)
16
08-06-2015 09:36 AM