Author Topic: Car stalls when braking  (Read 5196 times)

Offline emery1990

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Re: Car stalls when braking
« Reply #10 on: 28 March 2011, 17:13 »
Take out all the injectors, including 5th injector and check if they are all working/ spray pattern. This is exactly what my car was doing, I just put in a stand alone ecu so never sold the problem.

You checked your warm up regulator.

When cold the engine needs more fuel, so the 5th injector gives extra fuel whilst cold, if one injector is bit weak I think it can cause these issues. Think resistance across the warm up regulator should be 22-26 ohms.

Offline cняis

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Re: Car stalls when braking
« Reply #11 on: 28 March 2011, 20:57 »
no one has suggested the idle screw yet. surely if its wound down so much the idle is set to, say, below 500rpm, the ISV will have to compensate to bring the rpm back up. hence the delay:


3. If I blip the throttle and rev the car, the revs come down and the car almost stalls (with the car stationary) but recovers.



if the CO mixture screw is messed with, the idle screw will also need to be adjusted IIRC


I don't think a semi will give the same results

Offline motah33

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Re: Car stalls when braking
« Reply #12 on: 30 March 2011, 18:22 »
Thanks for the info. I shall check the idle screw - I've pulled a few bits off it now.

I presume the 5th injector is also know as the Cold Start Valve? Does the Digifant have one because I couldn't find reference to it in any manual. Does it have a warm-up regulator?

This is what I did:

(a) I removed the air inlet hose so that I can see down the inlet manifold and it looked quite clean (I didn't move the flaps to look down the minifold).
(b) I removed the vacuum hose to the brake servo unit and found that the plug on the manifold was gunged up.
(c) I removed the vacuum hoses from the air filter housing to fuel pressure regulator etc (I'll change these hoses when I put them back). I found that the plug (next to the idle screw) in which the vacuum hose from the fuel pressure regulator goes into (through that T-splitter) was also gunged up.
(d) I remove the crankcase ventilation pressure regulator valve, and the hose, to find it was also gunged up.
(e) I removed the ISV completely and it looked ok but I'll give that a soak in some carb cleaner.
(f) I removed the hose from the inlet manifold to the ISV. This plug on the manifold and the hose looked clean.

Do I need to give the inlet manifold a clean out considering the pipes (b) and (c) were gunged-up quite badly. If so, is there a way of doing so using some carb cleaner? I'm thinking if I can I start the engine with the stuff I removed and somehow force the gunge out of the manifold?

Any advice is most welcome.

Thanks

Offline emery1990

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Re: Car stalls when braking
« Reply #13 on: 30 March 2011, 19:38 »
Could remove the throttle body and give that a good clean before and after flaps.

Offline rubjonny

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Re: Car stalls when braking
« Reply #14 on: 04 April 2011, 11:22 »
with the engine off look in the bay at your throttle body, open and close it manually a few times and listen out for the idle switch clicking. make sure it clicks off and on every time you open and close the throttle no matter how fast or slow you operate the throttle. if its a bit sticky remove the throttle cable and retry, if its better try adjusting the cable, set it so the throttle is just fully open when your foot is to the floor. if that still doesn't help change the cable.

next look at the wiring behind the throttle body, there is a 2 pin connector for both the idle and WOT switches, make sure the wires to this are ok. its common for them to snap back here. if it looks ok, start the engien then go back to the bay, open the throttle by hand slightly so engien revs are at around 1.5-2k rpm, then press the WOT switch on the top of the throttle body. the revs should drop, then rise back up again when released. if not, there is a break in the wiring to the TB, or the switches themselves are damaged.

note this test only confirms the wiring up to the 2 pin plug is ok, and the wot switch works. this doesnt check the idle switch which could still be broken, if you could reach underneath to press it then this would confirm the idle switch is ok, but its a bit tricky. you can use a multimeter to test it though, put it in continuity mode and touch the 2 pins on the tb. it should read an open circuit with the throttle off the stop, go closed at idle and closed at wot
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