been having this issue for awhile. showed up after a nasty impact with a MAJOR pothole a few months back. when i hit the pothole my throttle was sticking pretty bad, went to to shop and replaced my TPS for the sticky throttle. This issue appeared just slightly after the shop, became worse as time goes by. runs fine till i get to a certain area. my timing was thrown off as well by this pothole.....shop didnt adjust tps to my timing i have now, but was there before i adjusted timing and after. ive replaced these items all fuilds in car (tranny, oil, brake, steering (atf)) master brake booster throttle-body GASKET ONLY power steering pump rack and pinion e-brake cable front calipers cleaned and inspected these items iac throttle-body valve above booster (holds air one way and lets it go through the other way. happens right around 30mph or when im on the brakes around 1k rpm also i will mention that when i am at 40mph or so sometimes when i step on the brake the engine decelerates like im driving a stick and leaving it in gear and coasting (loud exhaust) or downshifting to be more accurate but only when i step on the brakes...when i let off the brakes it goes back to normal....... she drives great, nice power and everything.....ive had several different people look at this and their stumped. [video]https://www.facebook.com/video.php?v=690606484342541&saved[/video]
My guess is something broke in the AFM, have you got anyone you can swap with to test? Also check all your couplings in the engine bay, bad connections can cause weird shit Do you have a gearbox ECU?
Have you checked your throttle cable, I've had them get close enough to the exhaust manifold to melt the plastic cover and make it hard for the cable to slide inside the tube. It works fine under acceleration because your foot has enough strength to overcome the resistance in the tube but the spring on the throttle body isn't strong enough to make the cable return
Dave may be onto something? You take your foot off the accelerator when you press the brake. Sorry I don't see anything unusual in the video
no i havent got anyone to try the afm out with at the moment...... ive checked all the cables and connections........ in the video if you watch the "rpm" gauge you'll see it bounce around......all the sound if you can hear it changes like im downshifting. im an auto....lol
I could see it was an auto but thought it was "kicking down" Looks like clutch slip to me (yeah, your box is full of clutches), it may not be the clutches itself but there are valves and pumps (3) which can get clogged. My next suggestion is to drop the box sump and clean the filter etc, fill it with new ATF and see what happens If you lift the black AFM cover you can then see if any of the plug pins are broken inside, seal it with silicone when you put it back
Already dropped sump and put new filter in....video was filmed afterwards. Ill pull up the black part on the fan.
I will presume you have a automatic transmission... Have you inspected the automatic transmission solenoids the control fluid pressure that lockup of the gears..