90. fc with idle problem (video)
 

https://www.youtube.com/watch?v=IPVH...e_gdata_player





it does the hole cold start. but as soon it finishes, it bounces. i pulled the plug from the throttle body. & it smooths out at cold start revs. 3500 rpms

bump. edit video

anybody ?? help

Alright the first thing to check is for ANY air leaks from the throttle body to the filter box. The second thing I would check is your two adjustment points on top of the upper manifold. There should be a screw directly on top of the throttle body that allows you to adjust the throttle intake. Try adjusting that lower to see if it decreases that throttle bobble.

thanks any other suggestions?

TPS sensor perhaps, they go out constantly.

That thing is idling WAY to highfor being fully warmed up. First find the vacuum leak you have and fix that, then when you get it to idle at 750 fully warm set the narrow range tps to 1volt at the ecu.

Check the codes and see what you find. TPS will do that, So will the IAT.

thanks guys. more info the better!

Best way to check for vac leaks: Start it up and spray carb cleaner around the manifold mating surfaces and vacuum hoses. If it's sucking in unmetered air, the engine will suck in the carb cleaner at the location of the leak and speed up.

It could also be a stuck throttle plate, and is your timing correct? Did the car sit for a long time beofre you got it?

yes. it sat for awhile. the second ports are stuck also.

ill get a better video clip when i get off work.

not sure if this helps but i had a honda that did that, it was the mapping sensor

https://www.youtube.com/watch?v=37dA...e_gdata_player


updated video!

holy shit dude........

Have you checked for vac leaks? Have you flushed the coolant?

From the video it just seems like the thermowax in your TB isn't functioning right. My car hunts like that until it's warmed up all the way.

Your throttle plates could be stuck too.

You physically need to make an attempt to work on it, taking the suggestions we've made, and tell us the results.

You keep on asking "What's wrong" and have never made a post reflecting that you've tested our suggestions. Sorry but we can't help you unless you make an attempt.

That plug you pulled is the throttle position sensor. If the car doesnt see the tps signal it ignores it and uses the maf, map, cas, and h20 temp for timing and fueling needs. The car SHOULD NOT be idling at over 2000rpms. You have a air leak somewhere, be it metered(thermowax failed open, bavc open, aws open, throttle cable binding) or an unmetered vacuum leak...and a large one at that. Ignore the 6pi and vdi right now, even of those are stuck it wont cause the problem you currently have.

its definitely a vac leak combined with the TPS being most likely bad or out of adjustment

where's the "tps" located?

its the 2 black plungers on the side of the throttle body connected to that plug you are disconnected.

http://atkinsrotary.com/store/images...91T-TPS-01.jpg

i tryed the curb cleaner with ever hose & seal i saw. nothing happend,still did the bounceing. coolant looks soo nasty & smells bad. gotta change it. the tps is bad, i believe because when i push down on the throttle, the rpms drop alot. but still bounce. im taking it to dave at speed1 for a rebuild/streetport anyways.

check UIM, LIM for vacuum leak, check TPS, check BAC, extra ground etc. good luck!

when i do replace my tps. how do i reset my idle?

bad aws
 

My 91 NA did exactly the same thing all of a sudden. The accelerated warm up valve (aws on the driver's side of the UIM) was Stuck open or something. I just plugged up the hose and everything was fine.

Edit: Nevermind someone already posted my solution.