my car runs terrible

Cadillac Forum Cadillac Classifieds Photo Gallery Member List Calendars Search Contact CF Sponsors
Cadillac News Forum FAQ Cadillac Timeslips Cadillac Recalls TSBs Register Login

my car runs terrible

Printable Version

Cadillac Forums >> General Technical Section >> General Tech >> my car runs terrible

Page: [1]

Cadillac Forum Sponsor

General Tech Forum sponsored by Magnaflow

Login
Message << Older Topic Newer Topic >>

my car runs terrible - 7/3/2008 4:20:54 AM

jb632bb

Posts: 4
Joined: 7/3/2008
Status: offline hi I have a 92 caady. Its missing, hard starting, rough idle.. I checked the tps and o2 sensor, ended up at the stealership.. they said I have multec injectors taht are shorted... They want more than the car is worth to fix it.. So i am going to do it myself.. But, my question is how do i know if its really injectors.. i really don''t trust the stealership. What test can i do.. The car is a cream puff and only has 60,000 miles on it.. Why are the injectors bad

Post #: 1

RE: my car runs terrible - 7/3/2008 9:50:58 AM

carnut

Posts: 350
Joined: 2/23/2008
Status: offline Shorted means that the wiring harness to them shorted I presume. I doubt if the injectors themselves are shorted based on what you posted. If their repair is to replace the injectors then its unlikely all 8 are faulty. Given what you''ve said you did to diagnose a miss, I would get a second opinion from another shop. I dont think you have the expertise to ck wiring for a short nor the ability to replace injectors. Rebuilt injectors are offered on E BAY for less money than new. My car has 140,000 miles on it and has had one injector replaced because a piece of dirt got in it. So what I''m saying is injectors last well beyond 60,000 miles unless someone applies 12 volts to them which will short them out or somehow the wiring to them is damaged. Each injector has a wiring connector to it which can be individually disconnected to isolate the inop injector much like pulling a plug wire to determine a faultly plug or wire on an older engine.

_____________________________

2 1984 Eldos, 1991 Allante, 88 Allante (sold)

(in reply to jb632bb)

Post #: 2

RE: my car runs terrible - 7/3/2008 10:10:10 AM

stomper

Posts: 1447
Joined: 6/18/2007
Status: offline
quote:

ORIGINAL: carnut

Shorted means that the wiring harness to them shorted I presume. I doubt if the injectors themselves are shorted based on what you posted. If their repair is to replace the injectors then its unlikely all 8 are faulty. Given what you''''''''ve said you did to diagnose a miss, I would get a second opinion from another shop. I dont think you have the expertise to ck wiring for a short nor the ability to replace injectors. Rebuilt injectors are offered on E BAY for less money than new. My car has 140,000 miles on it and has had one injector replaced because a piece of dirt got in it. So what I''''''''m saying is injectors last well beyond 60,000 miles unless someone applies 12 volts to them which will short them out or somehow the wiring to them is damaged. Each injector has a wiring connector to it which can be individually disconnected to isolate the inop injector much like pulling a plug wire to determine a faultly plug or wire on an older engine.

the diag you got from the stealership aint worth much.

carnut has given you a better diag w/o even looking at the car.

BTW, the connectors to each injector are more likely to be the problem than the injectors themselves. in my many cars aging (15 to 22 yrs, up to 175,000 miles) fleet, i have never ever, replaced even one injector, however, the connectors have needed cleaning now and then.

make sure you also get yourself a new fuel filter.

< Message edited by stomper -- 7/3/2008 10:20:42 AM >

_____________________________

"If you're going through hell, keep going"
~ Winston Churchill

(in reply to carnut)

Post #: 3

RE: my car runs terrible - 7/3/2008 3:20:47 PM

jb632bb

Posts: 4
Joined: 7/3/2008
Status: offline ok let me try again.. got the car apart.. to check an injector i put an ohm meter on the terminals on the injector.. FSM says normal is 16ohm of resistance. I found 6 in specs and 2 have readings of 3.2 and 4.5.. so those injectors are shorted.. I ordered a set of the Bosch replacements.. they will be here saturday.. I will put them in and report.. This thing has not been running right for a year.. Lets see if the fuel injectors help..

(in reply to stomper)

Post #: 4

RE: my car runs terrible - 7/6/2008 7:40:47 AM

jb632bb

Posts: 4
Joined: 7/3/2008
Status: offline well I finally got this car running right. I got the new design 3 Bosch injectors from the Fuel Injector Connection. wwwfuelinjectorconnection.com for 169.00 for the whole set.. Beats 800 from the stealership. I put them in and bingo its perfect.. No more hesitation or stumble.. Started it this morning cranked over in a sec. I am so happy what a difference.

(in reply to jb632bb)

Post #: 5

RE: my car runs terrible - 7/6/2008 9:23:21 AM

stomper

Posts: 1447
Joined: 6/18/2007
Status: offline with the injectors now out, do the two suspects still show shorts?

_____________________________

"If you're going through hell, keep going"
~ Winston Churchill

(in reply to jb632bb)

Post #: 6

RE: my car runs terrible - 7/6/2008 6:11:52 PM

jb632bb

Posts: 4
Joined: 7/3/2008
Status: offline yes they do still show shorted coils.. I have been reading alot on these multec injectors that gm used between 89- 94,, They are not alcohol complient.. There is an epoxy seal inside the injector that insulates the fuel orfice from the coil housing. When this seal is gone the fuel leaks into the coil causing it to short.. There were serv bulitins on this from AC delco Advising not to clean or use fuel injector additive in the fuel in these years.. When the Multec 2 came out in 95 this problem was addressed. But, they still clog like any other injector.

(in reply to stomper)

Post #: 7

Login OR Register now to post a reply to this forum topic.

Page: [1]