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Well crap. All ready for 3 days of racing this weekend and ABC has gone crazy. When I parked the car at work after lunch today it felt like the right front rose up a little after I shut it off. I thought, that's odd. Started the car to drive home and when I put it in gear the right front kind of hopped up an back down. Red flags going off in my head now. Drove the car a few feet and parked again and as I sat with it idling in park it felt like it was lower on the left. Sure enough it is. Nothing leaking & ABC fluid level normal so I head home.
In a short distance the car is leaning left and I get the red STOP CAR TOO LOW warning. I pull over and the car levels out. Goes up and down with the height button. No leaks. Fluid level ok. Try to drive and the left slowly drops. Stop the car and it levels out.
Sucks because I'm all loaded up to go to the track, camp & racing this weekend. Even worse is it's the last racing for the year here. Already have race gas, a brand new set of drag radials mounted up yesterday, food, firewood, etc. all loaded up just waiting to get off work and head out Friday night. All that was left was to wash the car and bolt on the new tires tonight. Now I'll spend the last race days of the year either trying to figure it out or waiting on parts.
Any suggestions? Please don't say coil overs, that doesn't get me racing this weekend.
You can start by cleaning the valve body and installing new seals and hope the takes care of it. Your pump may be going out and the tiny bits of metal are starting to contaminate your valve block.
It's home in the garage now. I'll hook up the SDS and see what shows up.
First time in my life paying for a tow. Oh well, saved me a couple hours to unload everything out of the trailer to haul the car, then put everything back.
Ok I'll take a look. The left rear value (the corner that dropped when I was driving) seems way off from the others when the car is sitting level on the ground.
Check the level sensor mechanisms, the strut top connectors plus the nearby acceleration sensor connectors. SDS is probably key to seeing what the the system thinks is going on
matt, sorry to hear this. hope you get it sorted quickly. nick seems to be on the right track and it's probably a sensor, or even better a disconnected sensor. hopefully you just reconnect and your good to go. my guess would be level sensor, but i believe your star will show that..
good luck!
Looks like it's the valve block sticking. Showing a bunch of codes, but sensors are all working as when I move the car they show results consistent with car movement.
Using my SDS I set the car to roll side to side and the right front corner does't drop. The left goes up & down, the right rear moves up & down, but the right front just hangs up higher then it should ever sit and barely moves. I tried pitch (front to back) and got the same result, the right front is up high and barely moves. Finally did full rodeo just to see it since I've never done it and again, almost no movement of the right front. Kind of looks like a stripper hanging onto a pole, one corner stays put and the rest jiggles, LOL.
Sorry, gotta laugh or I'm going to cry. Getting ready for this weekend I spent $700 on new drag radials, $655 on a new voltage transformer, $450 on MS109, $800 on new trailer tires..... Next race days for me just changed from Saturday, Sunday, and Monday to waiting 7 months for the next day the track is open. Oh and the weather is supposed to be cool this weekend, track prep is the best it's been all year, lots of friends going to the track to race and spectate...... Virtually no chance I can get a new valve block before Tuesday. I could take mine apart, clean and rebuild it, but would I then trust it at 130 mph with no time to test it other than the drive to the track? Uhhh, No. Not when the car collapsed so far my tires rubbed last night and I had to get it towed home.
Change your filter and check the fluid. Your pump may be going soon. May be a good time to convert to.coilovers. I'd imagine.you would be able to get a better launch with adjustable coilovers than the stock ABC.
Just did a filter a few weeks ago. Fliud is about 2 years old. Doing Rodeo at idle it starts at 190 bar and while rodeoing dropped just under 170 bar. Any idea what normal drop during a rodeo is?
That's fine, the pressure has to stay near 180 bar so you're perfect. Seems like it's a sensor in that strut or the passage to the r/f in the valve block. If you can move the car and the sensors don't move, and you can't actuate the level manually via SDS, has to be the valve block.
Yeah, that is what I thought too. I can get a little movement on that wheel and it's sensors all seem to correlate with what I observe physically. I can't get a new VB until Tuesday and after talking to jnash as well I think the solenoid itself is the issue so, I guess I'll bite the bullet and buy a whole new VB.
sorry for the bad news. didn't you rebuild that valve block? is there a way to check the solenoid to see if it's bad? rebuilds and used valve blocks may not be the way to go unless the solenoids can be tested. good luck and enjoy the holiday in spite of this set back.
Just did a filter a few weeks ago. Fliud is about 2 years old. Doing Rodeo at idle it starts at 190 bar and while rodeoing dropped just under 170 bar. Any idea what normal drop during a rodeo is?
That's the lowest rodeo pressure drop that I've heard of. 120 to 130 bar is common.
I'm not certain, but I don't think its necessary for the pump to maintain 190bar. ABC works on a short duty cycle, the short terms demands are met by the accumulators, and the pump spends most of its time recharging them.
During rodeo, the demand is continuous, so I can't see how the pump should be able to keep up. The struts are probably going up and down as fast as the pump can pump them. That's not normal operation. Its a bit like revving the engine in neutral and saying it doesn't generate any torque.
Rodeo does seem to give a good measure of the health of the system and the pump in particular.
Good luck,
Nick
Last edited by Welwynnick; Sep 2, 2016 at 01:55 PM.
Maybe it didn't drop much because only 3 out of 4 struts were moving??? Maybe it makes sense it wouldn't drop as much if 1/4 of the demand is not there so reqlly only doing a rodeo on 3/4 of a car, LOL.
Thought about it, but with my larger drag radials if the right front goes up and the left rear drops all the way like it is doing now the tire will rub hard. That could be bad at 130mph. Not really willing to risk it. If I had a week, or even a few days to drive around afterward and see how it's doing I would try that, but putting myself and another racer at risk when I know I could end up with a car control/handling problem and blowout is just not my way of playing. New valve block will be here Tuesday for a mere $1620.00. Cheaper than a totaled car...
A few month ago i had similar issues and the car would lower one corner while driving. Scared the crap out of me and the people next and behind me thought i was nuts. Hooked up the sds and tried my best to find an issue and was unable to. Turned out it was the abc computer itself. Bought a used one from ebay and it has been fine since. So if you cant find anything wrong it might be the computer.
Good luck.
Thanks Pill, sure hope it's the VB since I already ordered it. Was getting a code for a stuck valve and that is the corner that doesn't move so pretty sure it's the VB on mine, but if I install it and the problem is still there I'll keep that in mind.
This is bad news and bad timing for sure, but the upside is that you diagnosed an obscure ABC problem more quickly than any other owner has done before.
Let's hope so.... Going to head to the track anyway. Two different 5 second car owners offered me the chance to pit for them. One said I could sit in it and warm it up. Might be fun to start a 3000 HP blown alcohol injected motor.
Are the front strut sensors interchangeable left and right? In theory, if you could swap sides and it gives you the same problem on the left side you know it's the sensor, may be a quick fix assuming you can get the sensor. If you race in the high position of suspension, it shouldn't allow the strut to go up much resulting in the rear to sag and rub. Good luck.
Watching the sensors during rodeo, roll and pitch tests I'm pretty sure they are fine and all reading consistent with car movement. I even tried jacking it up while watching them and I'm pretty sure they are fine. Only possibility other than a stuck valve is a frozen strut but I don't see how that could happen.
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