98 SV help

Hey guys, need a little help.

I replaced the battery in my 98 SV coupe ...it was sitting dead for a while.

I did start it after charging the battery and it ran fine prior to replacing the battery...just not holding a charge.

After installing the new battery, it starts up and immediately goes to half throttle...and stays there. .5000 rpm.

 

I did find that the electric servo motor was pushing the throttle to half upon turning on

The ignition, and holding it there.

Any ideas?

Thanks

When did you get a 98 SV? I feel like every post you make its working on another new lambo! How many are you up to now? 3 Diablos correct? Sorry im of absolutely no help on this!

I suck at electronic issues but maybe a fuse or relay? That does sound out. Maybe magician JeffLambo will chime in

Sorry I have no idea..

When did you get a 98 SV? I feel like every post you make its working on another new lambo! How many are you up to now? 3 Diablos correct? Sorry im of absolutely no help on this!

Just got it last week. Now at 4 Diablos, a Murcie and a countach.

My wife is going to have me committed soon.

 

Thanks guys, maybe Jeff will know.

I tried letting it sit with the battery disconnected over night.....no luck.

As soon as I powered up the ignition...that little servo pushed the throttle half open again.

Needless to say, I did NOT start it.

Floor mat is not stuck is it?

are bothbanks running maybe only 1 bank running.when only 1 bank is running its running on 6 cyls and will cause low idle

Sounds like it could be the carter driver control unit.... certainly something in that area.

 

carter motor

Sounds like it could be the carter driver control unit.... certainly something in that area.

 

carter motor

It is definitely that piece that is malfunctioning...

Great info...I will check into this.

Thank you !

Well, digging deeper...I discovered that the engine is only running on 1 bank...

Anyone else ever had this happen?

I did try a search on the forum...but I must not be searching correctly.

And still no CEL's and no codes popping?

I vaguely recall a thread titled 6 Cylinder Diablo

you probably have a bad coil on that one side ?

i meant ign module theres one for both sides.

Carter Motor, and 5000 RPM aside, if the car starts up and runs on one side it's those stupid solenoid valves that are tied to the alarm system resting above the fuel tank. One has probably failed. You can confirm by disconnecting the fuel lines to each of the fuel rails. You'd have fuel coming out of one, the other not.

 

I think these are SV specific.

Carter Motor, and 5000 RPM aside, if the car starts up and runs on one side it's those stupid solenoid valves that are tied to the alarm system resting above the fuel tank. One has probably failed. You can confirm by disconnecting the fuel lines to each of the fuel rails. You'd have fuel coming out of one, the other not.

 

I think these are SV specific.

Thanks guys...I will check all of the above. I appreciate the suggestions.

IF the engine will begrudgingly accept your throttle input to raise the RPM, an easy job would be to pull off the distributor cap and take a look. I lost 7-12 when the cap and rotor catastrophically ingested itself (one rotor blade still alive servicing 1-6 contacts, button shot out, spring wrapped around the rotor, arcing everywhere, charred and melted rotor plastic). ...put the replacement cap/rotor on, back in business.

Check the common issues first. Does it have spark? Is it getting fuel? Youve narrowed it down to which bank isnt working. Issues ive had with mine the rotor would break apart inside dist cap. There is a high and low that controls each bank. A bad coil will have the same effect also. If none of that works, check computers. Each computer controls one bank. You can swap the plugs. Good luck

Guys this car has no distributor cap. A faulty coil shouldn't shut down the whole side of the engine either. My bet is still on the solenoid.

This is a COP car (coil on plug) I will agree that the fuel solenoid is a real good idea. You need to try to see if you have spark and fuel pressure. To check for spark you will pull one of the coils out and see if is sparks when cranking the engine. If it has sparks then check the fuel pressure.

uhhhhh. uhhhmmm.

 

 

ok.

This car has 3 coils per bank. One coil not working would only shut down 2 holes. Its not clear from post is it at 5000 rpm or 500??

 

There are engine fuses inside left rear fender behind the carbon panel. If one of the ign fuses is down then will run on one bank. If it is running at 5000 rpm then it can be related to the carter motor (thats the little piston that pushes the throttle linkage open for cold start. It has small ECU that helps bank 2 LIE (engine control unit) operate the carter motor.

 

I would check all fuses behind the carbon panel in engine bay left side first.

 

 

Then I would swap the plugs at the LIE both LIEs are the same one gets a ground singnal to know which bank its controling. When you swap the plugs the other ECU will take over the control of the carter motor.

 

Its normal for the piston of the carter motor to go out and open throttle for cold start this is what rases the ideal speed. As it warms up it goes back in. It uses the TPS sensor (throttle postion sensor) to know how far it has come out. Of the right side linkage is off or binding this can make it come out to far. Check linkage on right side of intake.

 

Is it idealing slow or fast one bank or two?

 

Jeff, PM sent. Thanks.

UPDATE! FIXED!!

Thanks to Jefflambo,

A blown 10A fuse in the engine compartment on the drivers side under the carbon trim panel.

It controls the passender side ECU.

 

THANKS JEFF!!!

UPDATE! FIXED!!

Thanks to Jefflambo,

A blown 10A fuse in the engine compartment on the drivers side under the carbon trim panel.

It controls the passender side ECU.

 

THANKS JEFF!!!

Thats awesome to hear! Simple fix!