IM new to tpi, buy my new iroc won't start unless I put starting fluid then it starts and runs forever(with rough idle and no horsepower). I was playing with the tps today then it started without the fluid and ran(still rough) then after I turned it off and tried again it won't start. Help!

 

It could be a number of things. Are you getting any SES codes? Ohms on your injectors? Fuel Pressure? Timing? Is it MAF or MAP?

 

I have to get my hands on a scanner the car was sitting for over a year and my other ones carbed so I got no tech tools lol

 

If it has sat, you may have some gaskets that have gone bad, and possibly injectors. Did you clear out the fuel system? Maybe replace the fuel filter? I'd check fuel pressure first though. Also, You might want to consider checking these: https://www.thirdgen.org/tpimod2
I know you said you messed with the tps and it helped, but you should still make sure it's adjusted properly so you can rule it out. Also, you can do this without needing a scan tool http://www.gmforum.com/1992-1999-91/...erclip-273720/

 

Ohk thanks is there something I can plug a pressure tester to? On the fuel rail? My car is an 89 iroc btw

 

There's a schrader valve on the passenger side rear of the fuel rail. It has a cap for you to unscrew; should be silver in color. If you rent the fuel pressure tester from autozone, it hooks right up to it, no adapters necessary (at least for the one I had).

 

Remove the gas cap and take a whiff of the filler neck. If it smells like turpentine you've found your problem.

 

non stabilized fuel and if you have the stock multec injectors , you need a complete fuel system overhaul from the pump up. Southbay fuel injectors has a great deal on there bosch 3s

 

check the MAF

 

I went through same situation. The fuel tank was shot. I changed fuel pump and new fuel tank flaushed lines and ran and it fired right up. Battled vac lines breaks everywhere but car was mechanically sound and idled well (albeit smokey and rough and crap) but no stalls or surging.

It was not until I replaced all the plenum, fpr, vac lines and gaskets while swapping the injectors and really blowing out the fuel rail and changing the thermostat that the car returned to normal. It all worked before but so bad it was not acceptable.

the FPR and thermostat and injectors were so fouled it was crazy.

Once that was done (I did myself and was not much $) just time. I reset the TPS/IAC and the car idles steady like a rock at 1200-900-850 cold after a minute of warm up then in drive sits at 675-725 with no problems. it fires up and doesnt stall.

Now it is tuning ECM since the injectors since I have some exhaust leaks with removed AIR and crappy cat back pipes causing some lean conditions at AE and PE.

as well as venting gas tank issues I think

 

I second this.. unplug the MAF see if it runs better, easy enough to do.

 

I think my car is map not maf, it's an 89 that's speed density still right? Anyway I unplugged the sensor before the throttle body and still nothing, when the car runs it would idle rough but consistent and rev up smooth just slow and when driven had no power

 

When I unplug the sensor it runs worse, the no start without fluid problem doesn't change though

 

I just went outside and tried to start it and it started no problem then I turned it off waited and tried again and no start

 

The $250 i spent on a tuner was life saver. I wondered about so many things since my car sat and just ran on fluid. I had no clue and can easily throw money at it.

The fuel was so bad it was hard inside the tank. Step one throw out tank and get a new pump for me. Not saying the same but if it fires then you know spark is good, I had vac leaks but it ran out just surged and lean a lot. fuel was #1

fix that and I bet you might have a car that runs ok

 

The gas is all brand new, the car had no gas, it's got fuel all the way up to the rails and it will run by itself after I start it with fluid, and I can rev it up n stuff

 

sorry misunderstood. so all stock, ecm too? so it fires up with fluid no problem and will idel with just fluid? ot just fires and stalls?

as for gas to the rail, you actually can prime the fuel rail to 40psi but when you crank it wont fires?

 

It's so weird it needs the fluid to start but after it starts it will run normally without fluid or anything! You guys think I should put some injector cleaner or sea foam in my gas?

 

Yeap All stock doodooo 305

 

If you like bandaid fixes sure go ahead

 

So I shouldn't try to clean it up?

 

You should drop the tank and work your way fwd, if they are multec injectors a better reason yet to replace the injectors.

 

you never stated the year since you said iroc I would assume its 85-89 maybe 90 .
if it is a 85-88 you may have a plugged or malfunction with the csi.

 

Yeah I hear multecs are crap, i did man! I said 89 iroc lol

 

could be as simple as sirty stuck IAC and your cold start is broken so low fuel pule at start. so with fluid it kicks enough fluid to light then stays on.

The stuck IAC (since you mentioned playing with TPS which also effects fueling) could be stuck open so it needs ot be richer to fire combined with bad cold start injector.

you siad it runs like crap anyway. so i would check the IAC/TPS voltages and response and replace the vac lines aroundf the TB and check timing and vac leaks before I fire it up again

 

I thought the 89 doesn't have a cold start injector? I'm gonna check out the tps, where is the iac in this thing?

 

I wasn't sure of the year.

could be the IAC or large vac leak and the fluid helps it crank over

or a weak battery too?

 

It cranks strong and fast, where is my iac?

 

And more news, when I unplug my tps there is no change in anything I can see hear or feel, the car revs the same, idles the same, and feels the same while driving

 

Unplugging sensors in not a very good diagnostic. The tps is a voltage feedback potentiometer grey wire is 5v reference and the blue wire is feed back. Koeo idle the feedback is .54 . Unless its over 4v you will have injector pulse. clear flood mode disables the injectors. You might look into a scanner or tunerpro rotten. Or start testing the cts resistance vs coolant temp and tps at idle. It could well be junked up injectors. You would be amassed how untreated fuel causes Barnes and destroyers rubbers parts in just over 3 months.

 

Somebody told me to check my cts because it causes no start, how do I check the cts?

 

 

My cts is good and my tps, I pulled injector plugs while it was running and all of them on the passenger side and one on the drivers side did nothing to change the idle. The drivers side exhaust manifold was really hot and the pass side not so much

 

Use a noid to see if you have injector pulse. I didn't see you post the injector ohms.

 

I used a light and I have pulse on the connectors. Will a fuel pressure leak cause it to not start?

 

Unless the fuel pressure is real low the engine will still try to start. Sputter when your cranking it. I have seen tpi even pop off around 15 psi. With the rough idle and now power
You need to verify good fuel pressure. If the fuel pressure is fine. It has to be bad injectors or weak spark. I'd does sound like a fuel issue though.

 

I switched the pass side injectors with the drivers side ones and now the drivers side has no fire, and with the wires sending a signal ok I assume my injectors are trash, what are good injectors I can buy? Keep in mind it's only a stock 305 I have like 180 horsepower so I don't need race injectors

 

Talk to the good folks at south bay. They can set you up with something.

 

i have an 87 iroc 305 i had a similar problem when i first bought it check the ohms of each injector if u have a haynes book it really helps. if the injector wont open no gas no gas no start. had two injectors out wouldnt start but the other six kept it running, rough but running. best of luck

 

+1 South bay

 

I bought the 305 injectors from South Bay, they are great and at a great price, my car runs smooth but it still lacks power and I'm throwing a code 42

 

the IAC (idle air control) is just under the TPS on the throttle body.it just screws out