I have the same car as you for 23 years now I had to replace 1 front ABS sensor not a bad job really .I found my problem with the fault finder under the bonnet on right hand pillar .I would get a new one of ebay about £25 Lexmark brand then disconnect each one in turn and try the new one the ABS which is broke will tell you . I can guide you further on this issue .my email is
jimliddy1@gmail.com. then possibly talk things through plus a few other tips on these engines .
Regards jim