20 Most Recent 1991 Audi 90 Questions & Answers

try putting oil in ur rear axle

1991 Audi 90 | Answered on Dec 03, 2017

around 850 is acceptable

1991 Audi 90 | Answered on Nov 22, 2010

check teh oil light pressure switch on the engine they often have a rubber boot over the wiring connections ,these boots tends to fill with oil throwing the oil light switch on ,must be a american market one because i have never seen this buzzer on the europeon ones

1991 Audi 90 | Answered on Sep 23, 2010

Bad relay to fans usually causes this and if computer is shutting it down over heating issues then means it's reading correctly from the coolant temperature switch meaning that's working. Given that the computer wants to shut it down and knows it's hot should mean it's sending the signal for the fans but no results because relay. Easier to determine if you have twin fans because if the fan motor was bad only one would not work.

1991 Audi 90 | Answered on Sep 02, 2010

Constant 12V+ N/A Go to Battery Switched 12V+ Red Ground Brown Illumination Blue Dimmer n/a Antenna Trigger White Antenna Left Rear Front Speakers 3 1/2" Dash Left Front (+) Green/Black Left Front (-) Orange/Green Right Front (+) Green/Black Right Front (-) Black/White

1991 Audi 90 | Answered on Apr 04, 2010

check for proper atf fluid levels, also check the fluid for metal sediments/debris and color should be pink,
possible worn bands; transmission needs rebuilt

1991 Audi 90 | Answered on Feb 22, 2010

it's an electric fan that turns on only when needed --by a temp sender in the rad (at about 92˚ - 105˚ F)

1991 Audi 90 | Answered on Feb 22, 2010

1. vacuum leak; check all rubber hoses for cracks
2. idle control valve; remove and clean with carb cleaner

1991 Audi 90 | Answered on Feb 22, 2010

is the pan loose or tight? if it's loose, but won't come down, it could the oil sump hung up on the windage tray, the windage tray goes between the pan and the block, it has a hole in the tray for the oil sump to fit thru, the tray is to keep oil from splashing on the crank, hope this helps

1991 Audi 90 | Answered on Feb 01, 2010

Fuel Filter: Locations
Located under the car forward of the fuel tank, near the fuel pump.


1991 Audi 90 | Answered on Sep 30, 2009

Audi used a sealant and when i do this job I bang a scrwdriver in between the block and the oil pan and prize it off.

1991 Audi 90 | Answered on Sep 03, 2009

It is mounted on the inside top of the fuel tank. If there is no access panel above the fuel pump inside the car, then you will have to remove the fuel tank in order to get to the pump for replacement. Pump as much fuel out of the fuel tank as possible before removing the tank.

1991 Audi 90 | Answered on Sep 03, 2009

do you have a manual

please rate my help to you if you dont have a manual please email me and i will tell you.
[email protected]

thank you.

1991 Audi 90 | Answered on Apr 21, 2009

i have the original book it says anytime the battery is disconnected it will do the lock up and read SAF on the display when this happens you cant use it again untill you unlock it... to unlock it turn the radio on the word safe will be displayed first press the am/fm button and then press the scan button and hold them down simultaneously until "1000" appears in the frequuency display release the buttons DO NOT UNDER ANY CIRCUMSTANCE CONTINUE HOLDINT THE BUTTONS DOWN OR PRESS THEM ONCE AGAIN THIS WILL CAUSE THE RADIO TO TAKE THE NUMBER "1000" AS THE CODE NUMBER. using the first four radio station buttons enter the code number found on your radio card (the codes you have) use button 1 to set the first digit of the code button 2 to set the second digit etc. the first digit of a four digit code must be "1" if your code number has three digits the first digit on the display must be set blank. Once the code is shown on the display press and hold the am/fm button and scan button simultaneously until the work safe appears in the frequency display release the buttons a radio station frequency will automatically be displayed ... MAKE SURE YOU PUT IN THE RIGHT NUMBER OR YOU WILL LOCK UP THE RADIO AGAIN AFTER 2 TRYS AND WILL HAVE TO WAIT AN HOUR BEFORE YOU CAN RETRY IT. IF YOU LOOSE THE CARD WITH THE NUMBER SEE YOUR AUDI DEALER

1991 Audi 90 | Answered on Feb 20, 2009

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