305 tpi car won't rev, backfiring...

[quasar34]

ok guys, so last week i was on my way to circuit city getting onto rt 17 and i went to punch it to get on the highway and the car just died.. got the car started as i rolled toward the highway and then the car wouldnt rev up as i gave it gas.. the car died again as i was on the highway so i rolled over into a parking lot in which i couldnt get the car to start for a good 5-10 mins.. once i got the car started it wouldnt rev up past like 2,500rpms and was backfiring like a mofo.. i decided i better get the car back home in fear of getting in an accident or stuck on rt 17..for the first few minutes the car would only go 35-40mph with the gas at WOT then as i got closer to my house decreased to about 15-20mph. car wouldnt start for a few hours later did the same thing..i let the car sit and didnt drive it untill 2 hours ago..

today my friend mike (maroman88 ) came by to scan the car to see if it threw any codes but it was no success.. started her up and it ran alright, so we took the car around the block and for the first half of my block the car felt ok as far as revving up and then it started acting up again.. top speed of 15-20mph and wouldnt rev past 2,500rpms.. got the car back to my house turned it off and now it wont start..anyone have a clue what this could be?

[GP99GT]

clogged cat?

[The Fixer]

The only time I had a similar problem with my TPI car was when the ignition module took a dump. That's underneath the rotor, inside the distributor.

[chrisfrom nj]

change the fuel filter i had the same problem in the 88 gta i drove it to west orange from garwood i was doing like 25 mph top speed

[SupermanX24]

Bang on the cat with a rubber mallet, see if its clogged. You'll hear a rattling inside of it. After that inspect the fuel filter. Let us know what happens.

[quasar34]

i didnt have much time to mess with the car today since i had class and work but i checked the cat and it didnt rattle or make any noises.. think maybe it could be a vacuum leak??

[Untamed]

Yeah change the fuel filter then run a detergent through the lines to clean out the injectors.

Are all 8 cyls firing? One or more spark plugs may need to be changed out.

[quasar34]

ok so heres an update..
Untamed - i put new spark plugs in about 3-4 months ago.. gunna try the fuel filter sunday..

i was checkin out the car a couple days ago and noticed that the bottom corner of throttle body gasket was sticking out from the side of my throttle body.. so, i put a new gasket on, and nothing changed.. I also put a new cap and rotor on after the gasket and nothing changed.. today i decided to throw in a new tps and that also didnt help.. i checked my fuel pressure and it was reading about 36-38, is that a little bit low? sunday, im going to change out the fuel filter and see if that helps any

[Batman]

Could be a bad module or coil also, that fuel pressure is a little low for a TPI, I think 42 PSI is normal if memory serves. Was that 36-38 static or under load? Did it drop sharply when you try and rev the car? If it did it could also be a fuel pump, injectors, filter or regulator

[quasar34]

alright so i just went to check out how hard it would be to replace the fuel filter and i went to start the car to back it on ramps and it wouldn't start.. i did notice that my fuel pump turns on and stays on for a second and then shuts off.. do u think this could be the problem?? maybe the relay of the fuel pump is bad?

[BonzoHansen]

Backfire? Maybe a module or pickup coil.

[maroman88]

i did notice that my fuel pump turns on and stays on for a second and then shuts off.. do u think this could be the problem?? maybe the relay of the fuel pump is bad?

the pump primes, once u put the key into the "run" position the pump will prime and then stop and then once you turn the key to crank it then itll start again and the car starts

[Slo86Bird]

my car has the same problem but mine wont stay running for more than 3 seconds. i was told it was the fuel pump/filter. i checked online and it said 60-65 psi and i checked the car and it was 33 psi. i am gunna change the filter to see if thats the case because my sister had that same problem in her f150 2 weeks ago and it wouldnt start so we changed the filter and ran great.

[V]

it is NOT 60-65 psi

[Batman]

No way is it 60-65, that is higher then an LS1. Let me consult the book of knowledge today and I will get ypu an answer, for some reason 42 is sticking in my head but that could be an LS1. MOST cars if the fuel pump is going bad it will still idle, then start to break when you add RPM, unless of course thepump is just dead. I am definately leaning toward a coil or module here.

Edit- 34-36 PSI is normal for static conditions in a 305 TPI.

[The Fixer]

I am definately leaning toward a coil or module here.

Edit- 34-36 PSI is normal for static conditions in a 305 TPI.

:werd: Like I said in my response waaaaaaaay above, I had that same problem with my TPI car, and it was the ignition module. Bring it to Autozone and have 'em test it. Since your car is a low-mileage Bird, the pickup coil is probably OK, but the module can die anytime.

[IROCdan330]

i had the same problem multiple times with my car, and the fuel pump crapped out each time...the first time it started and wouldnt rev past idle, then stalled and wouldnt restart until a ride on a tow truck. then it wouldnt recreate the problem unless it was put under load...the 2nd time my pump went it wouldnt rev past 4500 under WOT. The third time my pump went it would run but backfire like crazy and was ridiculously low on power.

I would check fuel pressure again, and if you can get it started tape a gauge to the windshield and take it for a ride around the block or parking lot...see if it falls. You may also want to check for volume of fuel, and voltage to the pump. you can start with easy stuff, like fuel filter (it probably needs to be replaced anyway), if that doesnt help...move on to the bigger.

Like said above dont count out ignition either...

[quasar34]

i thought the fuel pressure was supposed to be somewhere around 41-47.. ( i think 47 at WOT) also, i had the ignition switch replaced approximately 6-7 months ago, so i dont think its that...

today mike came over again and we checked out the fuel pressure again and it was reading about 36-38 at idle.. my dads friend said that if you pinch the return hose from the fuel pressure reg with a vise grip that the pressure would jump up, which would rule out a bad fuel pump since it has the capability to handle more than 36-38 lbs.. we tried it quick and it did what he said, the pressure jumped up quite high (i think it was somewhere in the high 40s) so im thinking maybe its the fuel pressure regulator?

also, today the fuel filter was changed and it didnt help.. also swapped out the coil with one mike had in his garage and that didnt help either... so far the things ive ruled out are: tps, fuel filter, cap and rotor, plugs, coil, ignition switch, cat..

i also have a distributor module that mike let me borrow to swap out and see if thats the problem but i havent had the chance to try that out..

[Slo86Bird]

me and mattywest changed my filter today and didnt do much. i was also thinking it was the regulator after i found out the filter did nothing. its either that or the pump itself in my car. idk about yours.

[IROCdan330]

i thought the fuel pressure was supposed to be somewhere around 41-47.. ( i think 47 at WOT) also, i had the ignition switch replaced approximately 6-7 months ago, so i dont think its that...

today mike came over again and we checked out the fuel pressure again and it was reading about 36-38 at idle.. my dads friend said that if you pinch the return hose from the fuel pressure reg with a vise grip that the pressure would jump up, which would rule out a bad fuel pump since it has the capability to handle more than 36-38 lbs.. we tried it quick and it did what he said, the pressure jumped up quite high (i think it was somewhere in the high 40s) so im thinking maybe its the fuel pressure regulator?

also, today the fuel filter was changed and it didnt help.. also swapped out the coil with one mike had in his garage and that didnt help either... so far the things ive ruled out are: tps, fuel filter, cap and rotor, plugs, coil, ignition switch, cat..

i also have a distributor module that mike let me borrow to swap out and see if thats the problem but i havent had the chance to try that out..

yea the other guys are talking about the ignition module, not the switch.

i would still vote fuel pump, as it seems when it gets warmed up is when it starts crapping out. get the car hot, and try doing either small powerbrake to load it or even just rev it up at stand still to see if pressure drops.

[BonzoHansen]

backfire is usually ignition issues, no?

[Batman]

backfire is usually ignition issues, no?

Yes, normally. Especially if it is out the intake. Change the module

[quasar34]

ok guys so ive been checking things out as i can cuz ive been workin a ****load lately.. anyone got any suggestions??
the car will start when sprayed with starting fluid then shuts down, sometimes it will idle but if you try to bring it off idle it dies.

heres some stuff..
1) changed fuel filter
2) spark plugs are ok (about 10k miles on them)
3) have spark (used 2 style testers, one with an LED and the other you set the gap and watch for spark...had plenty of spark)
4) used a noid light (blinks when cranking)
5) fuel pump runs (primes 2 seconds when turned to accessory)
6) checked fuel pressure (45 lbs when ignitions on, when it does run the pressure drops to 38 lbs.)
7) checked TPS (ok, also replaced with a new one and same thing, set at correct voltage)
8.) changed cap and rotor
9) pumped some gas into a glass jar and there was no water apparent
10) checked for codes, there were no codes just the code 12
11) unplugged MAF and there was no change..

could it be bad gas? any ideas would be appreciated.. i really need this thing on the road

[Fast92RS]

How much gas is in the tank? Try and put some fresh fuel in and try it again. Something still dosnt sound right. Try taking the cat out of the car and try starting it without the cat on. You got fuel, spark. Here is a dumb question? Is there air? Any stuff built up on the throttle body, try cleanig it.

[NJSPEEDER]

i would be looking at the ignition like som eof the others have said. coil, ignition module are both good candidates

[maroman88]

i gave him a coil and an ignition module

[quasar34]

yea the throttle body was cleaned when i put in a new gasket for it so its not gunked up.. the car has about 3/4 a tank of gas in it..the thing is i bought $10 of super at a Bp on rt 4(all out of regular) and then I bought $10 regular at a Delta in my town (river edge) and it started acting funky like 2 hrs after.. i dunno if its just coincidence or what but it seems kinda weird to me. maybe one of the places had bad gas?? is the ignition module the one thats at the bottom of the distributor?

[Slo86Bird]

i never run less than super in my car.

[The Fixer]

is the ignition module the one thats at the bottom of the distributor?

Yes, take off the distributor cap (don't forget to mark your firing order on it) and you'll see it held onto the base of the distributor, below the rotor. When you install the new one, make sure you put plenty of dielectric grease between the bottom of the new module and the distributor, or you will cook the new one.

[Untamed]

Clogged cat / too much backpressure?

[bubba428]

TIMING CHAIN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! on ignition module

[quasar34]

Clogged cat / too much backpressure?

do u really think a clogged cat would make it so the car wouldnt even start though??

Yes, take off the distributor cap (don't forget to mark your firing order on it) and you'll see it held onto the base of the distributor, below the rotor. When you install the new one, make sure you put plenty of dielectric grease between the bottom of the new module and the distributor, or you will cook the new one.

cool, thanks for the info.. ill make sure to do that

[blackbird615]

quasar34... i have the same exact problem with my car. before it got really bad, the car was lacking power, getting 2 miles to the gallon and belching out unburnt fuel.

when it got real bad, my car completely failed to start and drive. to start the car, i have to spray starter fluid in the intake. it'll run "EHH" for about 5 minutes and then it seems as if the car is missing on like 6 cylinders and can't get the RPM's up past 1000 (1000 if i'm lucky) or else it stalls out. i've replaced fuel filters, distributor cap and rotor, ignition module (the unit to the left of the distributor, i think thats what it's called.. long night), plugs, wires, o2 sensor, and set timing and cleaned PCV valve. still no luck

quasar34 i took my car to connor chevrolet off bloomfield ave in caldwell and they weren't of any help. i've had 4 mechanics look at it and were baffled. i threw codes hinting i had low spark at ignition module and my o2 detected lean running (wtf it was running rich!) and that was it.



i'm going out of my mind here... if YOU figure anything out, be sure to share it loud and proud because i know i'm sure as hell BEYONED baffled.


if i find anything out i'll post or PM

[maroman88]

blackbird, same car/motor as quasar?

[blackbird615]

1991 LB9 305 tuned port injection. i'd imagine he has the LB9 as well judging by his sig

1991 firebird trans-am WS6 yadda yadda


you ever heard of how to fix something like this or where to start? i wana know if quasar fixed his yet


-carmine

[maroman88]

nah he hasnt, n we got no idea wat to check next

[V]

back when i had my 88 GTA, 305 LB9, i had some weird issues, car would randomly stall out and such. Took it to one shop couldnt find anything, codes that came up werent any help. I took it to a second shop that had worked on the car previously for years for the previous owner(washington garage in bergenfeild). They had it fixed in a day, they put a new ecm in it and all was fine and never did it again.... maybe try a ecm?..worth a shot at this point.

[blackbird615]

i guess i could try that. how much does an ECM run you or what did you pay at the garage?

[quasar34]

i bought a new ecm and tried it 2 days ago and its still doing the SAME EXACT thing its been..i really have no idea what else to check..

smokingss.. u think i should bring my car to the place in bergenfield u mentioned? me and my dad dont know what else to check.. the thing is i dont really have the cash to bring it somewhere but if i have to i wanna bring it somewhere thats atleast pretty knowledgable with thirdgens so they can pinpoint the problem and won't rape me out the ass

[maroman88]

checked ESC and MAF, nothin new... i pulled 2 plugs, the front 2 on the drivers side after cranking the motor for a while and one was dry and one was damp. now when my 88 wouldnt start the plugs would be soaked to the point they were dripping with gas when cranked alot. fuel pressure is good, im thinkin maybe clogged injectors (mulitple injectors)? we cranked the motor with the plugs out and no gas sprayed out. maybe the fuel rail is clogged?

also the car will run when you spray starter fluid into the TB, but once it burns off it dies

[The Fixer]

Yes, take off the distributor cap (don't forget to mark your firing order on it) and you'll see it held onto the base of the distributor, below the rotor. When you install the new one, make sure you put plenty of dielectric grease between the bottom of the new module and the distributor, or you will cook the new one.

DID YOU CHANGE THE IGNITION MODULE YET??????!!!!!!!!!!!!!!!!!!!!

Oh, and Blackbird615, the part you changed is the ignition coil, not the module. Follow my instructions above for how to change the module. If that still doesn't do it, it could be the pickup coil too, but they only tend to go bad if the car has well over 100K miles on it.

[The Fixer]

i pulled 2 plugs, the front 2 on the drivers side after cranking the motor for a while and one was dry and one was damp. now when my 88 wouldnt start the plugs would be soaked to the point they were dripping with gas when cranked alot. fuel pressure is good, im thinkin maybe clogged injectors (mulitple injectors)?

Remember, the TPI is a batch-fire system. Injectors 1,3,5,7 are on one fuse, and 2,4,6,8 are on a separate fuse. It seems a little suspect that one entire bank of injectors wouldn't fire, so check the fuse too.

[maroman88]

i gave him an extra module i had laying around from my 88. yea i know there on 2 banks but it got dark and i just pulled the 2 easiest to get to lol

[blackbird615]

my distributor is rusty as all hell so before my new one came in, i tried to get some of that rust off and it ACTUALLY started without starting fluid.. call it a fluke? no my friend i call it a lead!! WOOOO

probably a fluke but it gave me an excuse to be excited... we'll see if thats the problem. if not, i'll check out my ignition module. if not, i'm going to bergenfield and bringing my car where you suggested

i'll update my situation when the new distributor comes in


-carmine

[quasar34]

got it towed to my mechanic this morning.. will update

[Icemansghost]

Its probabaly a bad fuel filter

[quasar34]

fuel filter was one of the first things i replaced

[quasar34]

********UPDATE*******

ok so my mechanic was goin crazy for a couple days tryin to figure out what the problem was..first he told me that my fuel pump was definately good.. i told him that i replaced the computer but he thought it might have been the computer anyway so he swapped it out and the problem persisted.. he then found that when he was using the noid light to check my injectors it didnt seem like it was lighting up quite as bright as it should.. he investigated some more and found that one of my injectors has a short in it and is causing this whole mess.. the thing is he allready has about 3 hrs labor into the car and told me that the total would be 1,300 if he replaced the injectors. First thing, im 21 and dont have $1,300.. secondly, anyone think hes rippin me off? he said its an 8 hr job.. Third, do you think it'd be better off if me and my dad just pay him the 3 hrs labor hes got into it, get the car towed back to my house and replace the injectors? is taking off the fuel rails, plenum, and injectors all that hard?

[IROCdan330]

no its not hard at all...maybe the manual says it takes 8 hours but it wont take you that long at all.

i still wouldnt be suprised if fixing that doesnt fix the entire problem though...i figured that would just cause a misfire.

i have a full set of 305 injectors (19 lb/hr) if you need em....theyve got 61,000 miles on them. i would recommend soaking them in injector cleaner, and they should be good to go.

[Batman]

8 hours for injectors? Take the car home and do it, it takes about 2-3 for a beginner. $1300 is rediculous. If you need it I'll drive down there and change them out for you for free. There are plenty of people who can give you a hand with it onthe board. Buy a new set of injectors and get that car home! While you have it apart would also be a good time to check all the grounds in the harness. If one of them is off you'd be surprised how bad it f's everything up. Also, if it hasn't been mentioned (don't feellike reading all the posts again), when you cleaned the TB you took out the sensors right? The last 4 TPI cars I've worked on with similar problems all had a bad TPS (some had other problems also). Food for thought. Maybe get a volt meter and do some snooping

[quasar34]

well hes allready got 4 hours of labor in diagnosing the car before he found out it was the injector.. then add another 300 for the injectors plus the 8 hours for labor would be $1,300..i barely have the money to do the injectors myself but im gunna just tell him to pull the injector so i can drive it home (its like 4 blocks away from my house) and get my dad to help me put in the new injectors..


Batman: i switched out the TPS after i cleaned the throttle body with a brand new one, used a voltmeter to check it was set right, which it was and it continued doing the same thing..

anyone know if i need to take the fuel rail apart when i do this? only reason im asking is because arent there a bunch of o-rings i'd have to replace if i have to take it apart? i allready know im going to need new gaskets for the plenum

[maroman88]

mattttt ive done it like 30 times lol

[Zero4488]

Try the ECU, mine went bad in my 86 and cause a whole bunch a different problems with the car, but your FP is pretty low...I think mine was well into the 40 psi level....

[quasar34]

Zero4488: well the problem is one of the fuel injectors has a short..mechanic unplugged the injector and i drove it to my house..

so now i have a list of stuff im trying to order tonight:
BBK adjustable fpr
msd 8.5 mm super conductor wires
slp air foil
19 lb. injectors (ford racing or accell??)
complete tpi gasket set
o-rings for fuel rail

now i have a question as to what kinda injectors i go with..stock injectors are expensive, so thats out of the question.. i found a set of accell 19 lb. injectors for 269 and i found a set of ford racing 19 lb. injectors for 260.. i havent heard the greatest reviews on accell products so im thinkin i may go with the ford racing.. according to tpiparts.net theyre supposed to be reliable and not as prone to clogging. any opinions on them? from my understanding even though they are ford racing they dont need any mods whatsoever to fit, or do they?

[maroman88]

no mods, there all the same injector

[Batman]

Go with the Ford injectors.

[Zero4488]

well I'm going to give you the heads up, when I but the BBK FPR on my 86, it didn't fit, the adjustment screw was too long and hit the bottom of my plenum...just for a heads up...

[maroman88]

i have the BBK but i managed to get it to work fine, bumped up the pressure a few pounds

[Zero4488]

Idk...I tried changing the screw, and nothing got it to work, so I just put it back to stock....

[Predator86]

I didnt read through the entire thread so i dont know if this was mentioned but i'll say it anyway....check your distributor....I had an issue like that and it turned out to be the rotor...so check the cap and rotor if you didnt already

[conlinj]

My formula had bad injectors when I got it, causing the car to have a really bad idle. I picked up some used ford 19lb injectors (stock 5.0/4.6) for real cheap ($20) and they are good injectors. Buy yourself a gasket kit ($30-$40, comes with the injector orings) go slow and it's not a big deal you can get it done in a few hours just start early. It was my first time changing it and taking the whole tpi setup apart and I had them changed out pretty quick. You should be able to do the job for $50-$60 dollars.

-Jim

[Zero4488]

sorry to hi-jack, but what would make my FPR not fit right?

[quasar34]

ok so i ordered some stuff the other night from summit and tpiparts.net just waiting for it to come in the mail... i bought the ford racing 19lb injectors, injector o-ring set, tpi gasket set, fuel rail o-ring set, bbk adjustable fpr and msd 8.5mm super conductor wires.. total was 220 + 214 = $434.. probly gunna do a little bit of porting to the plenum also..

[conlinj]

Don't port the plenum on a 305 tpi car, it will just take away low end torque, I've made that mistake. Only thing would be to grind out the egr walls that block the throttle body ports.'

-Jim

[Batman]

:stupid: I wouldn't touch the plenum on a TPI car.