jeremymsl

So There are a few problems with my camaro, befor i begin ill say im a highschooler so i dont know that much car lingo, i know the basics but i dont know stuff like WOT or random stuff, (my dad probably dose cause hes like a car genius) so dont get too technical for me haha, and there are no mods besides flowmasters, the last owner had it tuned up a few months ago (distributer radiatior electic fans spark plugs, wires etc) and he had the the entire top of the engin rebuilt because the last owner let it sit for looooooong periouds of time and all the gaskets dryed out. The problems are that im getting 8 yes EIGHT mpg, and it fluctuates at idle ( i cant tell you specific rpms because my tach is off, i tried moorleys solution but that just made it worse) BUT it only fluctuates after i drive it turn it off then start it again. The first thing i did was look at the tps wich was at like 3.4 volts at idle so i set it back at 5.4 at idle cause from what iv looked up thats right? So i cant tell if that fixed the gas problem or not because my guage is retarded (yesterday morning after 30 miles i was full but then after like 15 more i was almost down to half again and if i step on it it gos up to 4/5 of a tank) and my dad says i need to give the computer time to et used to the change, but i may still need a new one cause i think there just a small small amount of hesitation every once and awhile when i step on it. But i cant affored 8mpg! And the idle fluctuating thing i want to fix cause i want this car to be perfect.

So theres my story haha, if it dosent show in my tag its an 89 iroc z 350 tpi with mas air flow, iv heard some people saying to chect the maf and egr but i dont know how to do that

Thanks to whoever responds, im sure this wont be my last post haha

jeremymsl

Update, just checket the engin codes and im getting nada, from what iv looked up maby egr o2 or maf? how would i check or replace those and how expensive? i know o2 is only like 20 bucks but thats it.

88IROC350TPI

Definitely replace the o2 sensor.... Mine went bad once and no codes ever got thrown. It would get terrible gas mileage and idle strangely just as you describe.

jeremymsl

Thank you so much, iv heard there are multipul o2 sensors on cars so where is the one i need to replace or one's?

305sbc

iTrader: (3)

The 1989 TPI engine has only one O2 sensor.
Although it may need replaced, I don't recommend the cheapie replacement piece as they have a very high rate of not working correctly.

I suggest checking for fuel leaks over the entire fuel system - from tank to injector to be safe.

The engine fluctuation you describe sounds like it could be a misfire, which is often ignition related - bad spark-plug or plug-wire, distributor cap, etc...

Your gas gauge behavior sounds to me like a problem with the sending unit in the tank. The float mechanism may be damaged, or you could have a faulty ground back there from the sending unit. It's not easy to get to.

After troubleshooting you may want to seek a competent mechanic that is familiar with this sort of thing.

jeremymsl

ya, like i said the last owner did a full tune up, plugs wires distributer so it cant b that, but ill check each plug just in case, and ya im gonna check the fuel system to, but i think 88iroc350tpi is right, because i didnt give it much though at the time but when i was putting a sub in i had to keep starting the car to see if the sub was working and all and i noticed that there was alot of liquit coming out my muffler onto the concrete and if the o2 sensor is out and is running to rich that would explain that too, so i think thats gonnna b the first thing i do, ill still proably do everything you said just to be safe too. minus the mechanic if the milage and fluctuating go's away.

305sbc

iTrader: (3)

The TPS should read between 0.40v and 0.50v at idle.
While you're checking for fuel leaks be sure to check the fuel pressure regulator. when they leak the fuel can get sucked into the plenum via the vacuum hose.

Grampa

Yeah, multiple issues here. Obvious things first.
Definitely replace the O2 sensor.
Check all the vacuum lines under the hood. These are prone to drying up, crackign,a nd leaking vacuum, which can and will mess up signals to MAP sensor.
If you were in the budget for it, you may well wish to just replace the MAP TPS and O2. I know the MAP sensor on a car I had was goofing up the idle, and mileage. The O2 will definitely cause these problems, improperly reading the oxygen levl of the exhaust. This tricks the computer into correspondingly increases the timing pulse to the injectors. In turn, you get shitty mileage.

Also the obvious is to replace the air breather if you haven't already.
Check the oil levels of both engine and transmission.
If it's automatic, check to see if it's dark, or smells burnt.

Check the brakes to ensure they're not showing signs of a stuck caliper(s) or slave cylinder(s). You said it has been sitting for long periods of time, and this all goes hand in hand with that problem.

Good luck!

jeremymsl

Alright well looks like the first thing im going to do tomorrow is replace the o2, then my dad has the next day off so then were gonna clean out my throttle body and check all the hoses for leaks and all and check the fuel pressure air filter change the oil and all that and maby change the spark plugs. after all that hopefully ill be all good, thanks for all the help! Im really suprised at how great this site is, i didnt even expect to get one person to help much less all this, i already love this site haha. Thanks everyone, after everything ill post how it all went and if it worked haha

jeremymsl

Alright just rplaced the o2 (took 2 damn hours to get it off but only 10 min to put the new one on!) and went ahead and seafoamed the vacume and nex time i fill up ill do the fuel and ill proably do the oil tomorrow, but i can already tell its running better, cant know for sure about the fuel econamy yet but im keeping my fingers crossed , thanks again for all the help!

84CAMARO28inFL

jeremy they like your car better than mine. My car ran for the first time two days ago and i have to bug the hell out of people for answers to my car's problems.

I hope that doesnt continue and ppl help me with my camaro, i need to use the car soon so i really need your guys help and i thank the TWO ppl that helped me so far!

84 Camaro 2.8 Auto. Thanks

84CAMARO28inFL

ttt

to camaronewbie

Ok im really excited im trying to get myc ar going. I think about it at work etc and maybe ill use it for great things. I like the car it ha a good engine and trans. Yeah, today i smelled gas, someone is coming by to check it out tomorrow and well see whats up with that. I have a few ideas about the engine, it runs well and feels STRONG we just have to see whats happening.

camaronewbie thanks for explaining things a bit yes i too have a life and am low on cash, the Camaro im very very enthusiastic about and i do hope i can get those issue slicked. Maybe even pressure test it too

I still see my gauges "flick: when the car turns on and off, they dont seem to work when it runs. i cant see any display on the oil pressure, temp, and battery gauges! This is minor issue compared to gas smell and smoke/steam when the cap was on (?) but its something i should look at.

Tips? Thanks!

jeremymsl

Alright so today i checked the vacume lines and everything checked out, the fuel lines are good too, and i already averaged my mpg and half the tank was befor i did anything to fix it so it was at around 10mpg so i cant wait to go through this next tank to see my true mpg , thanks for all the help everyone! Im gonna run a can of seafoam through this tank of fuel to, i have yet to do the spark plugs, thatll b in a few weeks proably, then im gonna seafoam my oil and change it then too, but so far the signs are good and i think its fixed, thanks again!

miatanut5

Hi, all the above suggestions are good. If after checking all that you still have poor mileage, I would suggest checking the resistance on the injectors. If one or more ohm low it will cause the computer to inject too much fuel giving you low mileage and a stumble at idle.

jeremymsl

ok what the heck! after all that im only getting 12mpg!!!!! and a good portion of that was hwy! i mean could it be cause i idle for so long in the morning when i go to school? i idle for a good 20 min? but that was only like a day for this tank, i would adjust the idle speed but my tach is off so i cant tell if its high or not.

jeremymsl

ok update, so that angered me enough that i decided to do a 15 mile test, i filled up, drove 15 miles as normally as i could (i tried to be as evenly city as i could, not stoping constantly but enough and had the heater blasting and headlights on and everything) and when i filled up after (a little under) 15 miles (15mpg is my acpted mpg, thats what i want it to b) the first click was at .5xxx gal, 2nd and .8xxx gal and 3rd at 1.00xx gal, so that is 15 mpg AT LEAST but its looking like more sense i made it click 3 times and when i filled up i only think i only did once or twice? So maby it is from me idleing so much on the way to school? ill try to just turn my car off on the way to school when im stoped, opinions?