RPM pausing @1000rpm's when down shifting...

[Fried One]

Hi Guys,
Any suggestions as to why my rpm needle will pause at 1000rpm when down shifting to a stop. It is very annoying. The rpm's don't drop down like it should.It remains at a bit of a higher rev when going to shift back in 1st. I would have to wait a few seconds to continue. Any suggestions? Thanks!!

[Dark_5.0]

Check for vacuum leaks. Clean the cylinder shaped sensor on the side of the throttle body it may be sticking. Use some brake cleaner or something.

[GhettoPop]

Clean IAC, set TPS voltage, clean TB

i have aa similiar problem, cleaning the IAC and TB helped a lot but did not fully solve the problem. I have yet to set the TPS voltage but I think thats the problem, someone else let me know if i'm wrong

[Hethj7]

Doesn't the computer also try to hold revs a little higher before dropping all the way down for emissions reasons?

[Fried One]

Thank you for posting,
I will try cleaning out the cylindrical sensor on the side of the throttle body and see if it helps. GettoPop you mentioned the IAC ... am not fimiliar ? What does it stand for?I have a 92 lx and I believe the TB is coated with a special coating and it needs to be cleaned a special way.Are any of you familiar with this? Hethj7 my car never use to do this before. I have had a few instances where my rpms would rev up while driving I think it would be idling at 1500rpm. I would have to pull over ,pop the hood. I would check the tps (not loose) ...eventually I would shut down the motor and it would start up and idle normally. So since it did that I now have this annoying rpm drop and stick. Gonna clean out that sensor and see. Thanks.

[Coupe50h]

IAC- idle air control, or IAB- idle air bypass, same thing.

Yea brake cleaner always works good for me, i think all 5.0's hang a little before they drop the revs, it's a ecu thing. but it shouldnt be that noticeable, your tps voltage needs to be checked also.

[GhettoPop]

Originally Posted by Fried One

Thank you for posting,
I will try cleaning out the cylindrical sensor on the side of the throttle body and see if it helps. GettoPop you mentioned the IAC ... am not fimiliar ? What does it stand for?I have a 92 lx and I believe the TB is coated with a special coating and it needs to be cleaned a special way.Are any of you familiar with this?

IAC = IAB = the thing cylinder attached to the throttle body

as far as the protective coating, i always use GUMOUT TB cleaner, works great on TB and IAC. some people say not to harm the protective coating since spray cleaners may/will remove these coatings. u know what, if the TB is gummed up the coating is obviously not working! use a rag soaked in cleaner and clean the crap out of it, then run the car and spray some more in there to get the hard to reach areas, especially where the where the moving parts are.

i would also clean the MAF with some electrical contact cleaner, some use TB cleaner as well, but i have only used elec contact cleaner.all in all, I am fairly sure your TPS is your problem.

http://www.corral.net/tech/maintenance/idlereset.html

[Fried One]

GhettoPop,
Thanks for posting, I cleaned the cylindrical sensor today. Used Motomaster throttle body cleaner. It was not gummed up or that dirty. Also checked my pvc valve while i was at it. It too was moving freely. Had a bit of oil on it though. Is that normal? Could I use WD40 to clean out the MAF. I am not sure how but I will check it out.
I hope I don't have to set my TPS. This is my second TPS sensor.I have not loosened the screws since. My rpm seems to idle steady but only sticks on the drop. So I am thinking it might not be my TPS. What is the round thingy with round holes around the chamber..situated at the throttle body on the back between the TB and firewall. Could that sensor not need cleaning as well. I know there is a spring loaded chamber in there. I will also clean out the TB as you suggested. I know it is a bit dirty as I took a rag and just wiped some of the carbon in there. I was always skeptical to use any throttle body cleaner due to the coating.

[Coupe50h]

DO NOT USE WD-40 for the maf, use something that leaves no residue, like electrical contact, rubbing alcohol, or brake parts cleaner.

Im also pretty sure it is the tps voltage.

[GhettoPop]

NO WD-40! as stated above elec contact cleaner or something similiar!

I believe oil on the pcv valve. as long as you hear a clicking when u shake it, its good to go. The round thigy i believe is your EGR valve which i doubt is your problem.

trust me, soak a rag in TB cleaner and clean the crap out of the TB. then run engine and spray into TB as per directions on can. u'd be surprized how dirty it is and cleaning will make a world of difference in throttle response, and sometimes idle. i clean mine every 5k miles, as a matter of fast, i'll be cleaning it today!

i really think your TPS is the problem, its not hard to adjust man.

[HoodStrype]

Just my 2 cents... but you might want to go ahead and replace the TPS (throttle position sensor) as well if you haven't already. It's only $20. Set the voltage at .99 and that might do it if nothing else does. When mine went out it revved until it died, but who knows.