P1590 Starts won't idle
Still here in beautiful Northern Mich. without a running Land Rover. I could I suppose take it to someone but at this point I feel my very manhood is at stake. Recap: Head gasket repair BA head gasket kit, RAVE leading the way. Upon completion the thing started up after a fair amount of turning over and would promptly stall out afterwards. Does not want to stabilize at idle, giving it gas does not help and it stalls. Sometimes can get it to idle at very very low RPM but I shut it off as I feel its not good for it but did manage to throw code P1590 which I read is 3 Amigos which I would get occasionally when it was running before repair. The coder says P1590 vehicle speed control, idle control, aux inputs. In my previous thread the IACV was in question and it seems they may need cleaning plunger sticks. Disco Mike said not to mess with it as it could damage a good part. But in that instance it was about a misfire not stalling and unable to idle. I don't want to make it worse. I have ACE and SAI. Should have a video by next post. I am going to clear the code. Then see if it throws it again and I will do video so you can hear it. Never posted an attachment video so we'll see but I will try. Thanks again fellow forum goers.
Last edited by thehaz; Jul 21, 2012 at 03:57 PM.
Here is the link to my video. I don't think I'm cool enough to make it a click-able link but the address is good.
LR - YouTube
LR - YouTube
Coder is close, but the RAVE says:
P1590 ABS rough road signal circuit malfunction Hardware is OK, but SLABS ECU is sending an error signal
I guess the coder gets its idea as the D2 uses an averaged signal from the ABS to calculate vehicle speed.
As far as IACV, you clean them with carb spray, but you don't adjust the moving parts. They are a 180 - 200 position stepper motor, and damned delicate.
Attached page from RAVE covers that part, and fuses that run it. Would also want to be sure you don't have a vac leak or un-metered air betwen MAF and intake valves (hose off, top intake gasket, etc.) or sensor almost plugged in. Or shop rag in air pathway.
Last edited by Savannah Buzz; Jul 21, 2012 at 10:32 PM.
That video is good. Just like being there.
I would unplug and then plug back in the MAF and the Throttle position wires.
Also -
If you took the injectors out (which I did not do on my head gasket repair)
I would make sure you did not mix up the injector wiring.
And, check the spark plug wiring.
Also - the engine sounds really odd. Like there is huge vacuum leak.
Did you plug in the power brake line back in?
Black plastic line with a red retainer washer clip on it?
There are a few vac lines on there.
Are you SURE you put the upper intake manifold on right?
That it seated on the two hollow bolt pins all OK?
Are you sure that the upper to lower manifold gasket did not pop out or become smashed - partly on when you reassembled?
I think you have a simply reassembly error along the line somewhere.
I would unplug and then plug back in the MAF and the Throttle position wires.
Also -
If you took the injectors out (which I did not do on my head gasket repair)
I would make sure you did not mix up the injector wiring.
And, check the spark plug wiring.
Also - the engine sounds really odd. Like there is huge vacuum leak.
Did you plug in the power brake line back in?
Black plastic line with a red retainer washer clip on it?
There are a few vac lines on there.
Are you SURE you put the upper intake manifold on right?
That it seated on the two hollow bolt pins all OK?
Are you sure that the upper to lower manifold gasket did not pop out or become smashed - partly on when you reassembled?
I think you have a simply reassembly error along the line somewhere.
I have since my last thread, checked for rags or such in intake from air box to intake even tried with the MAF exposed. not attached to the air box. Completely removed upper intake from lower intake and removed all wiring connections. The upper intake is tough to get on right but I'm fairly sure its on right I know its on the two bolt pins. You could not bolt it down if it weren't. I did not remove the injectors. I also replugged all connectors making sure they are on all the way. I can remove the intake again and triple check myself but I don't know if it will help. I still have this coder I was mistaken before, it reads: Manufacturer controlled vehicle speed, Idle control, Aux inputs. If that is not relevant to my situation should I keep trying to start it and fish for more codes? Would a vacuum leak throw a code? Would unchecked air entering the intake throw a code? I could take more video if you tell me what to show. I also forgot to mention that after I try to start it there is a vacuum build up from the "coffee can" to the little black solenoid that is attached to the intake. Noticed it when I took it apart the last time. Pulled the one line off and it sucked a bunch of air up. Took the solenoid off and tried to blow through it and couldn't.
Last edited by thehaz; Jul 22, 2012 at 09:21 AM. Reason: forgot something
Cleared code and tried starting again. Now throwing two codes P1590 and P1668, coder reads: Manufacturer controlled computer, Aux outputs any info I've found on second code is that it an alarm code. Had that problem once or twice before but it wouldn't turn over at all. Lock and unlock on the fob would cure it. I've cleaned the IACV with carb cleaner but no change. Had it running for almost a minute but the throttle is worthless doesn't feel like it's giving any gas. 3 amigos came on quickly but never got check engine to come on.
Hi,
Did you do the heads yourself?
Are you sure you got all the rods in the tappets OK?
I listened to the video again.
There is a lot of clicking in the video - like low low oil pressure.
Or there is clearance in tolerances.
As you took the heads off - the only thing taken apart would be the rocker shafts and the push rods..
Or it seems like a huge vacuum leak.
The brake hose is in I am gathering.
Not sure if the hoses for PVC on the valve covers require a lot of vacuum, but I would inspect those too.
Yeah, it sure seems like a big vacuum leak.
Thing hates to run.
Did you do the heads yourself?
Are you sure you got all the rods in the tappets OK?
I listened to the video again.
There is a lot of clicking in the video - like low low oil pressure.
Or there is clearance in tolerances.
As you took the heads off - the only thing taken apart would be the rocker shafts and the push rods..
Or it seems like a huge vacuum leak.
The brake hose is in I am gathering.
Not sure if the hoses for PVC on the valve covers require a lot of vacuum, but I would inspect those too.
Yeah, it sure seems like a big vacuum leak.
Thing hates to run.
THEHAZ, I have access to duplicate parts (my Cousin owns a 2000 DII), we had a friendly wager that the issue I was experiencing (Just did head gasket, then truck would start but not idle smoothly, and ultimately die, same as you I think) was due to either IACV or the MAF. Cousin went with MAF, I went with Idle Air, I was wrong. Popped MAF on and it ran beautifully. Now I didn't know the history of this Disco2, I bought it with a known blown head gasket, and I thought that is why the test drive (very short) sucked so badly, but I think the MAF was toast before I took ownership. I also had not plugged in (tight till it clicks) the Evap control module on the top of the intake, so that was the first code it came back with, then the 1590 once we corrected the unplug. My cousin had experience the 1590 in the past, and ultimately corrected his issue with a new (actually used) MAF. I have a new Bosch on order to replace the borrowed unit. I was able to find it locally (San Jose CA) as NEW BOSCH from my favorite parts store here in Silicon Valley (Winchester Auto) for $130. That sure deats Atlantic British. Don't buy Bosch rebuilt from O'Rielys though, so my couisn tells me, had a bad experience going that route. Hope this helps.. By the way, props out to Disco Mike, I do whatever you say bud, thanks for helping us Noobs out.
Also, if anybody is intersted, I couldn't bring myself to reinstall the coil packs in stock location, so I fabbed a bracket, bolted the packs to the drivers side firewall, and made up my own 8MM wires from 500ohm/ft MSD Street Fire Universal kit (a bargain at $40 a kit, with crimper), and although I don't have miles on the truck yet, everything is running good (in the drive way at least) so far. Will update when I have about 500 miles on it.. Let me know if anybody wants to see pics of the finished product.
Also, if anybody is intersted, I couldn't bring myself to reinstall the coil packs in stock location, so I fabbed a bracket, bolted the packs to the drivers side firewall, and made up my own 8MM wires from 500ohm/ft MSD Street Fire Universal kit (a bargain at $40 a kit, with crimper), and although I don't have miles on the truck yet, everything is running good (in the drive way at least) so far. Will update when I have about 500 miles on it.. Let me know if anybody wants to see pics of the finished product.


