rcm Posted March 26, 2011 Report Share Posted March 26, 2011 Well i have done alot to the car as most of you know and been running it some just around my place.Noticed theidle when cold is a little rougher and now when i press on the brakes it gets worse and let upand it will get a little better.Is it possible the brake booster is loosing vacuum gradually gettingworse and making it run rougher? Link to comment Share on other sites More sharing options...
MikeMeyerhoff Posted March 26, 2011 Report Share Posted March 26, 2011 Well i have done alot to the car as most of you know and been running it some just around my place.Noticed theidle when cold is a little rougher and now when i press on the brakes it gets worse and let upand it will get a little better.Is it possible the brake booster is loosing vacuum gradually gettingworse and making it run rougher? The brake booster can leak vaccuum. Simplest way to test is to disconnect the hose between the 1-way valve and the booster. It should store vac even when not running, so if you pull the hose you'll heare it hiss/suck. No noise= test it. Link to comment Share on other sites More sharing options...
rcm Posted March 26, 2011 Author Report Share Posted March 26, 2011 So if no noise when i pull the hose at valve then its bad? Link to comment Share on other sites More sharing options...
MikeMeyerhoff Posted March 26, 2011 Report Share Posted March 26, 2011 So if no noise when i pull the hose at valve then its bad?If there is noise that usually means its good because it was holding vaccuum. If it doesn't make a noise, there is a good chance its bad. you can do a suck test to be sure. Link to comment Share on other sites More sharing options...
The Rabbit1 Posted March 26, 2011 Report Share Posted March 26, 2011 another way is get in the car, press the brakes until they arew rock solid, hold the pedal and start the car, it should get softer. If your brakes were already hard before you started, then the booster didn't hold vacuum. If it doesn't get soft when you start it, then it isn't doing anything either. Link to comment Share on other sites More sharing options...
Indiana Posted March 26, 2011 Report Share Posted March 26, 2011 Check the hose where it connects to the manifold. That hose is thick with a softer liner that hardens on the manifold end from the heat over time and it cracks inside that soft part at the end and if you've had it off/on a few times those squeeze clamps won't get it to seal to the barb in the intake. Leaky seal effects those rear cylinders and you press the brake pedal and and its worse. You can take that one hose off, flip it around and put the softer end back on the barb then cut off a short piece where its hardened then put that on the check valve end. It will sort of pull the bends out of it but if you did eliminate the ABS you can do the same, flip the hose and rearrange them and get rid of that end of the hose that is hardened. Link to comment Share on other sites More sharing options...
rcm Posted March 26, 2011 Author Report Share Posted March 26, 2011 Well i already replaced hose to manifold because it was rotten on that end.This was a couple of monthsago.I just recently noticed a little rough idle more since i started pressing the brakes,and now if i hold the pedal down you can tell it runs rougher.If i unplug it from the booster and block off end ,then start the car if it runs better wouldnt that tell me the same thing its bad. Link to comment Share on other sites More sharing options...
Indiana Posted March 26, 2011 Report Share Posted March 26, 2011 Test your check valves maybe they are oily and not seating. You could try to wash them I guess if they were. On the other end you could try and pull vacuum on the boost with a hand pump and see if it leaks. Link to comment Share on other sites More sharing options...
rcm Posted April 20, 2011 Author Report Share Posted April 20, 2011 Well it seems the booster may be ok i had a vacuum line come loose from bottom of tb,but it still seems to me it idles a little rough cold and gets somewhat better when up to temp.It does have the solid cam but dont know the lift or duration.They are set at .006 and .010 .I still was thinking maybe the delphis have a different spray pattern?I have a one wire 02 and a 2.5 inch exhaustwith no precat. Link to comment Share on other sites More sharing options...
grsmnky81 Posted April 20, 2011 Report Share Posted April 20, 2011 have you tried doing the tps/isc reset precedure? cold they will run i bit different than when warm. are you sure all ur temp sensors are good? temp sensor tell the ecu engine temp so it knows when to lean or ritchen fuel under hot/cold conditions. O2 sensor good? thats another determaning factor in fuel management. how is your engine timing? have you checked for any other vacum leaks? was the car originally built with mechanical rockers? are you running factory cam? i had an idle issue with mine, wound up being the schinder POS i installed, 284H cam. Link to comment Share on other sites More sharing options...
rcm Posted April 20, 2011 Author Report Share Posted April 20, 2011 already did tps reset ,idles at 900 rpms,new cts,timing 10 btdc,All vacuum hoses replaced.My post of 12 pages has covered all of this back a few months ago when injectors flooding. Link to comment Share on other sites More sharing options...
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