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I installed my new 1.7 and have been encountering unclearable flooding/fouling with virtually every attempt at starting. I say "attempt" because I usually end up giving up. This was a car that NEVER flooded prior to this. My only other coincidental changes are swapping the stock fuel pump for an FD unit and installing an HKS topmount intercooler. I have new plugs and wires on the way, but the old ones were firing everything up very reliably 2 weeks ago.
Any ideas about what could be causing this problem? I didn't think an FD pump would overpower the pressure regulator, but I suppose that might be the problem. If not, this ecu has serious issues.
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Whether or not the flood clear feature of the ecu is working isn't really a big issue. I've pulled the EGI fuse, used my kill switch, tried the Rtek flood clear procedure; it is just flooding so badly and soaking the plugs so badly that none of these things works. The only way I've managed to get it cleared at all is to pull the plugs, spin the motor with them out (clouds of vapor coming out), heat the plugs with a torch, reinstall and crank. That worked once, but didn't work again last night. One thing I need to check is the OMP linkage to the TB; every time I pull the plugs they are very oily as well as wet with gas; I don't know how much oil I should expect to see with the OMP functioning normally, but I'm sure seeing a lot.
Re: the injectors; I still have the stock 550's in both rails currently. Since installing the Rtek I've only started the car (twice; many more attempts) and taken it out for a brief run around the block each time, keeping the rpm under 3000 to avoid staging into the secondaries. The 720's are going in today along with a Brian Cain modified throttle body. New plugs and wires are on the way as well. I'll have the shop check the TPS while it's in. They're not too knowledgeable about rotaries, so hopefully they can figure it out.
By the way, I emailed Henrik last night as well as posting here.
I'm surprised even after all the warnings we give, you still decided to drive it with 550/550. Did you do any damage? Probably not if you really kept it slow, but why risk it just so you can take a 10kph drive around the block?
In any case, if you're still flooding with the MPI fuse out, its not an ECU problem, it's an injector problem. Maybe you had a leaking injector and the new pump made it worse. Or a compression problem. Have you done a compression test? What is your base fuel pressure set to?
Make sure the TPS is properly set up on the new throttle body as per the factory service manual. An improperly set TPS creates all kinds of problems.
> They're not too knowledgeable about rotaries, so hopefully they can figure it out.
I'm surprised even after all the warnings we give, you still decided to drive it with 550/550.
The staging point where the secondaries come in is 3500 rpm with the 1.7, correct? Am I wrong, then, in thinking that as long as I used very light throttle and kept the rpm below that level that whatever injectors were in the secondary rail would not be a factor? Believe me, I was very conscious of this issue at the time and watched my tach carefully.
[/quote]In any case, if you're still flooding with the MPI fuse out, its not an ECU problem, it's an injector problem.[/quote]
I don't think it's continuing to flood with the fuse out; it's just that once the car is flooded it doesn't seem to clear very easily. When I spin the motor with the plugs out it does seem to clear, and there doesn't seem to be any new fuel going into the rotors.
[/quote] Maybe you had a leaking injector and the new pump made it worse. Or a compression problem.[/quote]
Possible, but I'd never had any flooding problems of any kind with this car prior to the 1.7 upgrade, and the car flooded but cleared and started the first time I started it after putting in the upgraded ecu, which was before I changed the pump.
[/quote] Have you done a compression test?[/quote]
Not yet. Car had been running and performing well prior to this.
[/quote]What is your base fuel pressure set to?[/quote]
Stock fpr as far as I know; will have this checked.
[/quote]Make sure the TPS is properly set up on the new throttle body as per the factory service manual. An improperly set TPS creates all kinds of problems.[/quote]
Will do
[/quote]> They're not too knowledgeable about rotaries, so hopefully they can figure it out.
Theres the first problem. [/quote]
My local shop hasn't had the car in yet for any of this stuff; they can't be blamed for anything up to this point. My point is that they will be on a bit of a steep learning curve helping me to figure things out. I am taking the car to a rotary specialty shop (400 miles away, however) later in the week for a previously booked S5 turbo changeover and a couple of other things, so if we haven't got things figured out here, hopefully they'll be able to with their greater knowledge of 7's. And, no, I won't be driving it unless the shop here manages to get things up and running properly first. I'll be loading it on a car hauler otherwise.
This is likely a real stupid question but you have an S4 TII right? You have not mentioned this on your inital post. The Rtek1.7 does not work on an S5.
You can start the fuel pump by jumping a wire in a yellow connector (I think it is yellow) on the passenger side fender. If you look in the FSM you can find more info there. Here is a link.
Have a look at page 4B-69 and 4B-74. It describes how to do it there.
This is likely a real stupid question but you have an S4 TII right? You have not mentioned this on your inital post. The Rtek1.7 does not work on an S5.
You can start the fuel pump by jumping a wire in a yellow connector (I think it is yellow) on the passenger side fender. If you look in the FSM you can find more info there. Here is a link.
Have a look at page 4B-69 and 4B-74. It describes how to do it there.
Yes, it's an S4 (88). You have me a little confused here; why would I need to jump a wire to start the fuel pump? I can hear the pump running when the ignition is on...
Hold on, here...I was just looking at another thread in the 2nd gen section in which posters are stating quite definitively that the the fuel pump should NOT be running when the key is in the ON position but the starter isn't engaged yet. My pump, as I mentioned in the previous post, can definitely be heard running as soon as the key is ON. That was the first thing we did after putting in the FD pump; turned the key on and listened for the pump to make sure it was working. So, 2 questions: Could that be responsible for the flooding at startup, and how come the pump is running when it isn't supposed to? The only thing we changed in installing the FD pump was to run a little ground wire from the top of the pump holder to the frame. Could that be jumpering the pump? Wow, that would be such an easy fix.
It shouldn't make a difference....unless you have a leaky injector(s).
I could not imagine the extra ground wire, installed as you describe, would do anything to keep the pump running.
I can't either, but I'm grasping at straws here. Perhaps the problem is in the AFM, then? Might make sense, if the pump is running when it isn't supposed to; AFM maybe stuck slightly open, combined with higher pressure from the FD pump, might create a problem with a leaky injector that hadn't shown up before. Plausible?
My trusty guys at my local shop phoned me tonight with a very pleasant background noise; my Turbo rumbling away happily in the shop. During the day they had prepped my modded throttle body for install and then pulled off my newly installed topmount intercooler and the original TB plus the UIM to change the secondary injectors. What they found is both embarrassing and a valuable lesson. First a little background. When I received the intercooler, it had been packed in foam peanuts, but not wrapped or bagged. As a result it had peanuts up inside the end tanks. My son and I spent a fair amount of time cleaning them out and thought we had them all. We were wrong. When Curtis and the boys pulled the ic and tb, they found peanuts plugging the secondary butterflies and a few that had slipped by and were plugging things up in the intake manifold. You can figure out the rest. Once these little buggers were cleaned out, the new injectors installed, the new tb mounted and the ic back in place, the car fired right up with no problems. So, I am a) really relieved that the problem is corrected and that it was a simple fix; b) mad at myself for not getting all the packing out, even though we did try, and c) a little choked that the seller didn't take the trouble to bag the intercooler before pouring in the peanuts. Those end tanks are DEEP with areas that are inaccessible to fingers. In retrospect I guess we should have hooked it up to the shop vac to make sure it was cleaned out. Anyway, the project is back on track. Thanks to everyone who posted with suggestions and advice, and I'm really looking forward to seeing what the 1.7 can do in conjunction with all the other mods either done or about to go on. By the weekend the setup will include:
Cone filter, ported S5 turbo, Greddy Profec B Spec II boost control, HKS tmic, 550/720 injectors, Brian Cain modded tb, Racing Beat 3" full system, FD fuel pump, and of course the Rtek 1.7 ecu. Should be fun.
Thanks. I feel pretty stupid about this. We really did think we had the intercooler cleaned out, but if we'd taken a minute to do some suck and blow with the shop vac just to be sure I could have prevented a lot of headache.
Okay; just back from the shop in Calgary where they changed my turbo over to a ported S5, removed the ACV, and got the basic plumbing in for the EBC. Took the car for a run last night, and even without the Profec online, boost is significantly quicker and lots more of it than before with the combination of (inhale) the new turbo, the rtek and the 720 secondaries, the modded throttle body, the full 3" exhaust, and the new topmount (exhale). The car does start and idle VERY rich; I'm usually using my kill switch to shut down rather than just shutting off the ignition, which reduces the chance of flooding the next time I start up. Fuel cutoff is the standard way of shutting down airplane engines (which I've been doing for 20 years) so I have no issues with this. The other thing I've noticed is that with a cold weather startup the car won't idle for a few minutes; have to keep my foot on the throttle for a while before things smooth out and it will stay running on its own. Is this a common issue? It's not really a big problem, I'm just curious if it's the norm; I've seen a few posts from 2.0 users mentioning this phenomenon, but not so much from 1.7 users. Maybe that's an expected byproduct of an ecu that's programmed in Phoenix when you use it in Moose Jaw, SK! I'm thinking they don't have a lot of opportunity to test for subzero starts down there...
Any comments from the RTEK guys? Thanks.
By modded TB I assume you mean they did the TB mod? If so they got rid of the thermowax system which bumps the idle up until it is warmed up. It gets rid of the coolant lines to the UIM and makes removing it much easier.
I have the same thing but I dont mind warming it up for a minute.
By modded TB I assume you mean they did the TB mod? If so they got rid of the thermowax system which bumps the idle up until it is warmed up. It gets rid of the coolant lines to the UIM and makes removing it much easier.
I have the same thing but I dont mind warming it up for a minute.
Yes, it's the "full mod"; themowax removed, ported, polished, secondary butterflies removed, etc. My AWS wasn't really functional anyway; it would only go to about 1500 when cold; ironically, now I have to hold it at 3000 or it quits.
Turbo2ltr: Yeah, I definitely DO need to run through the whole idle speed setup procedure with the new TB; there wasn't time at the shop in
Calgary, although the TPS was checked and was within spec. Currently the car still wants to idle at about 1300 even when fully warmed, and it was really surging last night after my test drive. I'm pretty sure that's mostly related to the new TB, since when I did my very brief, low rpm test drive after putting in the 1.7 and before the TB went in it was idling nicely at 750. Interesting that the 1.7 was developed in BC; mind you, they rarely see temps below freezing on the coast. Their climate is absolutely tropical compared to a prairie winter, which we're getting a serious (early) blast of right now; current temp is about 0 degrees fahrenheit.
By the way; good luck with your medical!
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