19th Dec 2003, 07:18

I have a 90 Acura Integra with shift lock problems also.. It only occurs when temps drop to 30 +- degrees or colder..can't get key out of ignition and have to use a second key in the shifter release.. from what I have researched this could be a problem with the solenoid.. an adjustment is necessary or possible replacement. I am about ready to try this adjustment and see if that solves the problem. It doesn't seem to me if the problem only occurs when temperatures drop that the entire assembly would be bad. If this were true the key could not be removed in warm temperature either. An adjustment seems logical due to contraction/expansion of metal in varying temperatures thus throwing things out of adjustment. I would appreciate responses to this theory. Hopefully tomorrow I will try to prove it.

27th Dec 2004, 21:38

I have a '91 Intergra RS and same problem. I read a site last year where someone said that this was a problem with either the shift lock or the shift sensor. Unfortunately that web page is no longer up so I don't exactly remember which part it was, but it had something to do with a waxy build-up near one of these two components. This build up freezes when the temp goes down. The person on that web page just cleaned and regreased whatever part it was (now, I really wish I had printed the article) and the problem was gone.

31st Jan 2009, 20:13

1990 Acura Integra shift problem.

I have a 90 LS with the same symptoms, took a while to figure it out. BUT I HAVE THE ANSWER! The acura part# is 35700-SK7-A01, description is "switch assembly, inhibit". It's located on the right side of the shifter, and is made of white and black plastic. I think its 10mm bolts (2) holding it. I paid $53.25 (CAN) + tax from Silverhill Acura in Calgary. Got it in 3 days.

When you move the shifter from park, reverse, etc, a pin on the shifter fits into a sliding contact in the switch. This tells the ignition what gear you're in as you move the shifter back and forth. The electrical "brushes" that make the connections have little springs behind them to ensure good contact. There is grease in these springs, that over time, pick up dirt, dust, etc that gums up these springs, and prevents them from pushing on the brushes adequately to make good contact. When the temperature drops, this condition gets that much worse with the cold grease. When you put the car in park, The connection is not made in the switch to tell the ignition you're in park, thus, it won't release the key. This is why after you give the spring some time to put pressure on the brushes and make a connection you can remove the key from the ignition.

I took the old one apart and cleaned all the crap out of it. It works fine now, so I have a spare. Use needle nose pliers to pinch the black tabs on the switch body to get it apart. It'll snap back together.

I hope this helps someone before they go through the same hassle!

4th Jun 2009, 14:21

My 1990 Acura Integra GS 2 door automatic has over 160,000 miles and hasn't had a single problem. It still is running great. In my opinion Honda make very good cars. But my solution to your problem with the shift lock would be just to take the shift lock out.

6th Nov 2009, 13:51

Answer from 31 Jan is absolutely correct. Last year I cleaned the switch on my 92 LS and it helped some but now that the weather's getting colder the interlock problem's back. Those contacts are wear parts and will need replacing eventually. I just ordered the part from the local Honda dealer at $56 US plus tax. If you're at all handy with a screwdriver and socket wrench, get yourself a Haynes manual for the correct steps for removing the console cover (have to drop the lower dash panels first, easy), and go for it, rather than paying for shop time.

20th Mar 2010, 19:54

I know this was posted like a year ago, but great info on the switch assembly. I took it completely apart this morning, cleaned and re-greased. It's like it's brand new... You saved me like $300.

22nd Jun 2011, 17:36

1991 Acura Integra RS

Previous 2 entries talk about low temperatures and shift lock reset problems. I live in south Florida and my daughter's car has same problem. It's associated with RPMs. What we are seeing is not a problem but perhaps a symptom. When she parks her car, why was the engine idling at 2,000 RPMs? This seems to be the magic number that triggers the solenoid to engage the shift lock-out. Speed sensor problem? Dead rat caught in throttle cable? ECM malfunction (junior swapped out xBox CPU for ECM)?

A better question is how do you bypass this mechanism so we can damage our own car if we so please? The car is clearly designed by lawyers.

27th Dec 2015, 21:07

I know this post is super old, but does anyone know how to separate the black box from the whitebox? I have no idea how to do it without breaking them. I tried applying a flathead screw driver to the little back tabs, but they won't budge.

10th Jul 2016, 20:17

I am currently having this problem in the heat so I am perplexed... I can understand the metal contracting and changing the tolerances, but what about when it is expanding? Such is the case... Seems to happen in the heat... have rolled it back and forth using the shift lock key and it starts without an issue... any ideas? The car is a 1991 Acura RS.