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jeremy
08-04-2006, 11:00 AM
I've been slowly building up a 2nd gen 7 to race in IT (should be finished by the time no one uses them anymore). The car has been stripped and put back together with the bare essentials, however I can't get it fire and run properly. I was wondering if you guys could take a few guesses at this. Here are exerpts from another forum that hasn't been much help. If this is out of context for this forum, just delete this thread.

previously.....car would fire for one second and die. turned out i completely missed putting a bolt in two of the omp injector holes on the lower manifold. after taking care of this the car will fire up and idle roughly. however it will only do it with the afm unplugged and the throttle adjustment screw all the way out to acheive a ~500 idle. as soon as the afm is plugged in, the car dies. the idle is pretty rough as well. i checked all the sparkplugs for spark when i couldn't get it to stay running. they are fine. the cas adjusted all the way to one side smooths out the idle. i moved a tooth or so over but it never fully cleared anything up. i'm sort of stuck at this point. it runs smoothest with the timing retarded about 5*. i thought maybe the broken section on the vdi manifold (vdi manifold has now been replaced but with no change) was causing a vacuum leak, but i sprayed starter fluid on the area and didn't get any change in idle. i've sprayed just about everywhere looking for vacuum leaks without having found squat. another note is that the idle speed increases when i pull a vacuum line off.

ok, bought a vacuum gauge. rough idle at 500rpm netted into the needle bouncing from 5-10. holding my foot on the pedal to hold 1k netted in the needle bouncing between 14-15. another note is that the car is half driveable until it warms up. once it warms up, you can't touch the throttle w/o it stumbling and possibly dying. now i've never checked vacuum but i'm guessing the needle shouldn't be bouncing. when i revved the motor cold, the needle would hold solid as i revved up to 20-30 on the gauge.

bought an afm and ecu for 50 bucks. not bad on the price, but didn't make a difference. took the intake off AGAIN. replace any vacuum lines that hadn't been before. checked the caps. put it back on and had the same damn problem. soooo, i plugged up the extra afm to the connector and had mandy hold the plunger in. car fired up and idled same as with it unplugged. as soon as the afm plunger is let out, it dies. i'm replacing the fuel pump this weekend.


http://i11.photobucket.com/albums/a171/b136624/rx7003.jpg
http://i11.photobucket.com/albums/a171/b136624/rx7002.jpg
http://i11.photobucket.com/albums/a171/b136624/rx7001.jpg

Eagle7
08-04-2006, 10:32 PM
Is there a chance that you've got an S4 block (rear iron) with S5 intake? If so, the stock configuration has an interference that creates a huge vacuum leak where the upper intake manifold meets the lower.

jeremy
08-06-2006, 01:27 PM
the motor is the original that was rebuilt (carbon locked). so unless there was a mix up during rebuilding, it should be all the original s5 parts.

MaxEnergy
08-06-2006, 06:49 PM
Are those pictures current? Do you have the Intake snorkel hooked to the AFM? Obviously it needs to be to run. Sorry if that was stupid but you never know?

If that's not the case are the air hoses to the snorkel plugged or connected. I sounds like an airleak is not allowing the afm to work properly.

Is the TPS adjusted? I would try reinstalling the CAS. Have the engine on the yellow pully mark and line up the dot on the cas shaft with the mark on the gear and holding the cas completely out of the hole position the cas (in mid air) so that the locking bolt is centered in the adjustment slot and then carefully holding that orientation slide it down into the hole.

jeremy
08-08-2006, 02:48 PM
snorkel is hooked up w/ the two small elbows capped, and i understand the need to ask silly stuff. i'm the guy that gets all the hard shit right and forgets something like lugnuts. ;)

i have not checked either tps, but they were working fine before the rebuild. the cas has been put in about 40 times and at about every degree available just out of shear anger. i have a feeling it's something small and stupid, but i'll be damned if i can finger it. i'm going to peel off the intake blockoff plates and redo those just to make sure they aren't the problem. i'll have to see if i can find the specs on the tps to check those as well.