Fuzz415

HEy TGO! ive been reading your forums for a couple months in anticipation of me getting an IROC. I just got a 89 IROC 305 TPI with 74K! on it. The car has been sitting under a car cover on my buddy's dad's ranch for 7 years, previous owner was some 30 something year old who used it as a second/hot rod car. Sorry, for the wall of text, just wanted to give as much info as possible

The car is definitely a project car, let me preface this post by saying i am a young guy who knows nothing about working on cars. I under stand basic concepts, but once people start talking about ohms, carbs, and stuff i tend to get a little lost.

A Boutthe car, about a year ago my friends dad's fired up the car and drove it for about a month, then all of a sudden one day the car just died while he was driving. He left it for a day and came back it fired right up and he drove it home and its been under a car cover for a year. Hes an airplane mechanic and he suspects its the fuel pump ( i have read and searched many a post on this site about how much of a bitch it is to change the thing, and yes i will be dropping the tank and not cutting an access panel).

Yesterday, we started the car and drove around his ranch (5 min car drive) car ran great, sounded great, responsive, and a bit dusty. We brought the car the the garage to throw it on some stands to pull the pump. while the car was idling it revved to red line, but the car has a high idle (1500ish) and is burning real real rich (maf sensor?). Once the car was warm we tried to get it on the car ramp and once we put the car in gear the RMPs dropped real real low and the car would bog down, the car would catch it but the car almost died. We did this about 3 times and on the third time the car didn't catch the revs and died. Car wouldnt restart at all. Everything is cranking and turning but it just wont start. If we let the car chill for 30 mins it will usually start back up and once we threw it into gear it would be hit or miss if the car caught the revs and didnt die. We can hear the fuel pump come on with the key on, although it doesn't to it every time ( possibly because the lines are pressureized)

We changed the fuel pump relay at the beginning of the day. I have bought a fuel pump and strainer from napa (airtek) and will be going up to change it out this weekend. I just figured with the wealth of knowledge here if it is possible that its not the fuel pump and possibly something else. I was reading that if one of my fuel injectors is bad that could possibly be the problem.

Looking forward to your responses guys, this forum has been great so far and im looking forward to being a permanent member, provided i can get my IROC running =P


Just trying to get alternate ideas before we drop the tank, see if its possibly the MAF, O2, or even the injectors. Thanks guys

camaronewbie

Fuel pump won't always prime - if it's only been a few seconds since the last prime, it won't. After a minute, it will again - so just turning key off/on/off/on wont make it prime everytime.

Usually the pumps just go out, and they are done. But anything is possible.

Fuzz415

Thats right, i remember reading that. Do the symptoms described, make it sound like it is the fuel pump that is going out? im just trying to figure out if there is anything else i can change before i drop the tank.

camaronewbie

I'd defintely do a fuel filter. Then I might loo at ignition as well. You said the car sat a long time - maybe the Ignition Contol Module in the dist has gotten rusty or went bad, or the pickup coil. I'd ohm out the plug wires to make sure there's no breaks there, maybe try new plugs. You can ohm out the injectors as well, I just don't know what numbers you're looking for. Can test fuel pressure at the Schraeder valve on the fuel rail with a pressure test kit ('free' rental at any major auto parts store). Can grab a can of MAF cleaner and TB cleaner and try those too.

The fuel pump isn't a terrible job, just time consuming - took me an 8 hour day by myself - the exhaust has to come out which is a PITA, and then wrestling the tank itself isn't easy. And usually something else breaks (like a panhard rod bolt, and end link, etc. if you are in the rust belt. But personally I'd exhaust all other possibilities that I could first. Granted at that age, a new fuel pump won't hurt at all - but it' very frustrating to do it and realize it didn't solve the problem. Good Luck!

If I knew more about TPI, I'd make more suggestions - but I'm TPI ignorant - what I mentioned above is basic though, and worth a shot.

Fuzz415

Thanks for that info, my buddies dad mentioned that when he first recieved the car 7 years ago, it went thru a full tune up, new plugs, new wires, i believe there was a new distributor (might be a new alternator, its the piece of equipment directly in the middle of the hood, directly in front of the fire wall it has 8 wires sticking out, i thinkits the distrubtor. My buddies dad said the car had been sitting for so long some water dripped on it and corrorded the unit and he had to replace.)

Ill check out the ohm tester, do i have to buy that? or do i rent that liek the fuel pressure thing from napa?

camaronewbie

Not sure NAPA does the 'free rental' on things - check autozone or advance. The volt/ohm meter you'll need to borrow or buy - get a digital one - can get cheap at harbor freight ... http://www.harborfreight.com/7-funct...ter-92020.html

lunaticinaZ

throttle position sensor........

Fuzz415

throttle postion sensor? im sorry i am unfamiliar with that. what does it do and how does it effect the car? how do i fix it?

henryd3

iTrader: (128)

You would be wise to cruise on down to your friendly neighborhood parts store and pick up a Chilton or Haynes manual for your car and read through sections pertaining to possible problems you may be having to familiarize yourself with some of the basic stuff that might make it go a lot easier while trying to figure it out. Good luck and have fun!

Fuzz415

HAHAH you sir are right, i actually have both, haha they came with the car my friends dad was like " you're gonna need these". Unfortunately, they are both up with the car approx, 2 hours away from me. Im just trying to gather up all the knowledge i can so i can go up there and spend the weekend getting the bad girl running. When i go up this weekend ill be sure to take pics to show everyone

BluFBdy

iTrader: (1)

your TPS measures how far open the throttle plates are which should allow a certain amount of air in, as long as the computer knows how much air is flowing in it can add the proper amount of fuel, if its out of range and it senses that its letting in more air, its gonna squirt more fuel in to compensate, but back in the real world it might be a 1/4 open and the TPS reads 1/2...causing over fueling. now keep in mind thats IF your TPS is off, theres a tech article on here to test it and correct it, if you cant get it dialed in id just throw down for a new one. Also like mentioned above check your entire ignition system, wires, plugs, cap/rotor etc

https://www.thirdgen.org/tpimod2

^theres the TPS and IAC link, id do both just follow the tech article

good luck!

Fuzz415

Hey guys thanks for all the info provided, Im gonna get down and dirty this week to try to fix the ride.

@bluefbody thanks much for that tech article... haha im stupid, i just foudn the tech article section.

Hey thanks guys, pics and vids soon!!!!

BluFBdy

iTrader: (1)

Well I'm on my droid right now so I can't link it but if you go to the main page there's a faq and then the tech articles, I get them confused a lot just read the list a bit finer and its all there

Plus_P

Hope your weekend of wrenching is going good on it. Definitly start with the fuel filter. Our recently acquired 70K '88 Formula had multiple driveability issues, many similar to yours. Fuel filter cleared up about 75% of them. It had red sludge in it. Good luck with your IROC, you will get the satisfaction of learning bunches about how all these systems/sensors interact.

Regards,
Plus_P