all4u

my 89 formy 350 surges, bucks and pops at lower rpms and there is no power but the SES light isn't on. I have a good tune up on the car and a new MAF sensor, screens still on it, new air filter, and a TPIS AFPR. When I disconnected the MAF to send the car to limp home, the car runs awesome! I got another MAF cause it was under warranty, and hooked it up, reconnected battery and still same problem. I got another MAF cause I know that there is a chance they are bad from the factory, hooked it up and same damn problem. Without it plugged in, car runs great. Could it be the knock sensor or what am I missing? Thanks for any help cause I'm really confuzzed.

jv9999

iTrader: (1)

You need a scanner to look at all the sensors. Something else is giving the ECM bad data. Putting it in limp mode makes it ignore other stuff too.

all4u

where would you get a scanner for pre 96 cars that is somewhat good and under $500? thanks

jv9999

iTrader: (1)

You can pick-up an Autoxray on Ebay (like this one http://cgi.ebay.com/ebaymotors/AUTOX...spagenameZWDVW )or use your PC and a cable from these guys http://www.aldlcable.com/

doc

I have been using my AutoXray 240 since 1997. Great tool to help diagnose problems. they obviously do not sell the 240 model anymore, but this tool has help me out many times. Go into your local car parts store and see what they have over the counter.

John 89 Formula

Have you tried changing the maf sensor relays, most maf sensor problems are caused by bad relays, they are the 2 oval shaped ones by the brake booster.

all4u

I'll give the relays a try tomorrow and see what happens. Is there a way to swap them with a fan relay before I actually buy them to see if they are bad? Just wondering.

irockid43

I know this is an old post, but I am having the same problem. Disconnect the maf and it runs great. otherwise it runs terrible when the engine is hot. Did you find a fix for yours?? any help would be great.