When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a 1989 IROC-Z 5.7L that has been sitting in various garages for ~ 10 years for various reasons (deployments, kids, etc...) that I am FINALLY getting into. I have diagnosed that the fuel pump is faulty, and wanted to pursue a fuel system overhaul (tank, fuel pump assembly, lines, regulator, etc.) over the course of the next few months. I've been looking around online and see a number of people recommending the Walbro 255LPH pump, but cannot seem to find a kit for the whole assembly with it. I'm reluctant to go start ordering parts before I have some confidence I am ordering the correct ones for my particular vehicle. My question:
Any part numbers available for fuel pump/lines/kits?
What brand is recommended?
I haven’t heard of those brands for fuel tank/sender.
the only think I would check would be the gas cap fit before installation. Some members have had to file down the threads for aftermarket tanks.
Rumor has it that the aftermarket tanks fit poorly, and lack the internal baffling of the later TPI tanks. Unless the tank is rusty, I'd stick with the stock tank.
My project car's plates expired in 2009. Aside from some stink, and some flakes, the inside of the tank wasn't too awful bad. I soaked up as much of the old rotten gas possible with paper towels, then hosed the thing out thoroughly with Dawn and water. A bit of scrubbing where I could get at nasty deposits, some shots of cheap carb cleaner, etc got the last of the nasty out. After everything was dry, the loose flakes of whatever were easy enough to vacuum out. A ShopVac with a short garden hose or 4ft length of heater hose duct taped to the crack and crevice tool made it easy to reach the far corners inside the tank.
The Walbro tank that is most referenced is the GSS-340. It's a 255lph high pressure pump. Unless you're running a lot of mods (power adder, NOS, supercharger, turbo) you probably don't need that much pump, and you'll probably find it noisy. http://autoperformanceengineering.co...s.html#gm_apps is a proven vendor if you want to go that way. Personally, I went to Rock Auto and ordered a stock replacement pump. If you want to get fancy the 89 Turbo Trans Am/GN/Sy-Ty pumps are drop in replacements with theoretically higher pressure/volume, whatever...
Don't use the single sided fuel pump sock filter strainer. Look for the one that's twice as long with the pump clamp in the middle. The longer strainer is the 1LE type used in all the later tpi cars, but the short single sided part is often substituted and is a downgrade.
You want the ACDelco TS18 or TS44 (4th gen).
Beyond that, a new filter and a good set of injectors is always a good idea. I wouldn't mess with the rest unless it's actually causing a problem. At most I'd flush and blow out the lines.
Acdelco ep241 is a good pump, if your going through the whole fuel system check out southbay fuel injectors and fuel rail o-ring kit.
thanks Brian!
we have all fuel compatible fuel line..regulators, and injectors if need be. If you are interested in purchasing from us keep in mind that all tgo members receive 10% off. We'll be more than happy to help you.
I have Southbay injectors too. ...as do a lot of us here on TGO.
...I'm with Drew on flushing and blowing out the lines. I don't think there's a need to replace them unless you NEED to.
....and I'd also look into the Racetronix hotwire kit. I bought this whole kit, with the pump, and harness and everything. Granted I NEEDED more pump, but I was getting some voltage drop at the pump and just decided to get the whole thing. Basically it's plug and play, and uses the 12v from the original relay, but instead of powering that pump, it simply triggers the new relay on the Racetronix harness. I ended up bypassing the OE relay all together, but it's designed to be plug and play, and to use that OE relay if you want.
Look for the tag on the harness that plugs into the body above the transmission tunnel, in front of the gas tank. Pretty sure all the later cars are going to be the same sender, only the pumps and strainers are different.
Awesome-Thanks. I think I'm going to try to go with the Spectra FG20A fuel sending unit with the Walbro GSS-340. As of now I plan on emptying the tank and cleaning/reusing it. I will blow all the lines and clean up anything that needs some attention. I will update with pictures!
Well not off to a good start.... I got the pump and sending unit in the mail today. And it seems that the pump and the sending unit have different electrical connections. Am I just being stupid? Pics below.
When I did mine I got the tank and sender from Rock auto. Everything went together fine. But I went with the walbro pump. Called summit and told them what pump I wanted and what it was going into. No issues there either. Wish I'd have known about the longer screen tho.
If you got the pump kit from APE that I linked to earlier, it should have come with the pigtail. Even the Ebay Chinese knock offs should come with a pigtail. Unless you ordered JUST the pump, contact your vendor.
Fuel pump replaced, and the suspension is all still removed for cleaning/software replacement. I will address those questions on a separate post. But the car still will not fire. The engine is trying to start, but will not actually fire.
What I've done so far: Verified SAT spark by using the procedure in the Haynes manual (put distributor cable near body of car and watch the spark).
Checked that fuel is going to the engine by disconnecting the fuel line and observing fuel flow.
It seems to me that the fuel is not getting to the cylinders (clogged fuel injectors? Computer control signal? ) and I worry that the time the vehicle sat (~8 years) could have led to some clogging in the fuel rail.
Any guidance is appreciated.
Pics will follow soon! Thanks for everyone's help so far.
I'd put a fuel pressure gauge on the rail and confirm that you DO have pressure at the rail, and the it's good pressure. If you have that....I'd confirm the fuel is returning to the tank. I imagine you'd have way high pressure if fuel wasn't returning, but i'm just trying to cover your bases.
did you ever get new injectors? Stock 89 Multec injectors, having sat for years....ouch. ....and can you confirm the injectors are getting a fire/pulse signal? I bought a test light kit years ago, and while I rarely use it, it's proven invaluable when actually needed. https://www.ebay.com/itm/9pc-Electro...cAAOSwsB9WCO3z
Ok- please forgive my post formatting but I’m still in the garage. Fuel pressure is at 48psi at the test port and fuel injectors lit up when tested. I only tested one injector but figured they were all getting the same signal. Im struggling a bit here since it seems the fuel rail is getting SAT pressure and the injectors are being told to fire. Is this indicative of fuel injector clogging?
What do the plugs look like? If you're cranking the engine, and it's not starting, but the injectors are pumping fuel, then the plugs will probably be wet and smell like raw gas. If they've been in there during a LOT of cranking, they'll get fouled out.
Alright- I think the right course of action is to replace the Injectors, but this does get me started down the rabbit hole that I was honestly planning on attacking once the car was running. (Once the car is running I'll make a new thread I promise!)
Which Injectors?
-I think the answer you guys will likely give me is "depends on what you want..." so I guess I will really start to nail that down here.
My intention is to make it a show car (look pretty, sound good, and still function as a low end race car, although it would not see the track)
My budget is, well, ~15,000? I really don't have an overall budget but what I have is a monthly budget, so as it gets more expensive it just means I'll be an older guy sitting next to it in my $25 lawn chair at shows...
What I'd like to find is a build where someone turned a 350TPI into a ~350RWHP car and basically get their list of build parts.
For now- The injectors, this is what I was currently looking at. Please advise. https://www.southbayfuelinjectors.co...ctors-bosch-d3
Should I be selecting a higher #/hr now? Is 22 sufficient? I believe stock is 22.
Happy 4th! If any of you are in the Norfolk, VA I'm looking for a local network of Camaro nerds!
Those injectors may be pontiac only.... I guess I should be looking at this set instead, which is a significant price difference. Gonna have to make dinner for the wife or something if I'm to pull this one off in the next few days!
From: *member since 1999, I think - just can't remember my old name, and the big site crash...*
Car: 89 GTA ASC Conv., Prev: 89 GTA 6.3L
Engine: 5.7L L98 TPI
Transmission: 700r4 Automatic
Axle/Gears: 3.27:1 w/ JG1 Options:B2L, N10, U1A
Re: 1989 IROC-Z 5.7L fuel system overhaul
Originally Posted by YeahmanIROC
Those injectors may be pontiac only.... I guess I should be looking at this set instead, which is a significant price difference. Gonna have to make dinner for the wife or something if I'm to pull this one off in the next few days!
First and foremost, sorry for the delay. We had another baby and she their required some hospital time for a virus.
UPDATE- IT'S ALIVE!
Car now runs, but will not idle well. In fact without active gas pedal pushing it will stall out. I plan on checking fuel pressure with it running, any other suggestions?
I will start rear end/suspension overhaul next, once I close out this thread.
Says the video is too large, I will have to figure out how to compress it.
UPDATE TO THE UPDATE: After replacing the IAC, re-setting the TPS, and checking fuel pressure I was still having issues.
Then I went to check something in the vicinity of the distributor, and it spun................
There wasn't a bolt there to be tightened to hold the cap in place.
I adjusted it about 5 degrees, and the car fired near perfectly.
......I'll time the engine and then close this thread with a video (how do you upload videos? lol)
