I had posted a thread sometime ago. The car would idle fine but when I tried to drive the car , it would konk out.. I had the car towed to shop for 50.00...they could not find the problem and told me to come get it....$50.00 to tow it back home. I basically ran out of what to do .. It could have been anything..bad plugs, bad ignitors, injector issues.....who knew....ahhhhh

GSL-SE addict thankfully saw my thread and was nice enough to drive 2.5 hrs to my home and help diagnoise the probem. He had these diagnosis tools and such and he check the engine, ignitors, plugs, wires ..... We then did ( or he did) a fuel volumne test and sure enough , fuel volumne was low.. Ie: the engine was starving for gas)...He then checked the fuel pump and the fuel lines all the way back to the tank.. all was good....the last thing was the tank.. we dropped the tank,pulled the gas lines in the tank and sure enough....there was the problem .The line in the tank was stopped up about 80% or more. the line had such junk in it it was amazing...

I am now going to clean the tank with a gas tank kit and replace the fuel sending unit.

Some of you who have similiar problems should keep this in mind....especially if the car had been sitting for a time.. rust , dirt etc was my problem and it could be yours...

FYI and I hope it helps you'all

chris

 

anyone know if MMO or some other additive can help dissolve or help clear up this built up junk?

Just curious

 

im going to check my fuel filter 2marow thax man.

 

Happy to help, Chris. It was amazing how clogged the pickup lines were. They were packed solid. Both the feed and the return. It looked like carbon build up, but I don't know how that could be. The funny thing is that the FSM doesn't even show a volume test for the SEs, but they do list the pump output. We tested pressure and it was good. The car would start and idle great, but it you tried to drive at all (even 5 mph), it would kick, sputter, and die. I left my fuel pressure tester on when he tried to take for a drive, when he tried to drive up the driveway, fuel pressure was dropping from 30psi down to 10psi.

I then said that we should do a volume test to rule out a blockage or a bad pump. For the SE, you are supposed to get 1,700cc/min (1.7 liters/min) at a minimum. We used a spare gallon jug, turned the pump on, let it run for 1 minute. There should have been close to 1/2 gallon, but there was only a small amount (probably 10 oz). We repeated the test just after the filter and just after the pump..same issue. Pulled the tank and there was the problem. Another clue is that his fuel pump was making a lot more noise than normal. This is because the pump was working so hard to try to get fuel through the blockage.

Something to check out if you are having similar problems.

 

yea when my fuel pressure regulator stuck closed my fuel pump would start to whine off and on. It would make this whaaww.....whaaww sound. It did it the first day i bought it, actually.

Was there a sock on the pickup line on the tank?

 

Yeah. The sock looked to be fully intact. It did have some of this same crud on the outside/bottom of the sock. We didn't see are rips/cracks in the sock, so somehow this stuff was fine enought to get through, but still big enough to build up and clog the line. As I said, but the pickup and return were really bad. The return was worse, but that may be because it is a smaller line.

I do remember about your FP regulator getting stuck closed. I was actually telling Chris about that when I was there. You were getting 65psi at the rail IIRC.

 

Very interesting. There have been many reports of clogged and rusted fuel pickups.

What can we say about this problem? Here are some things that have occurred to me:

1-seems to occur a lot in the east and midwest. Possibly from the cold weather cycle with low tank and possibly from water in the gas, along with other crud. Maybe we are spared this in CA because we have a different gas.

2-diagnosis may be difficult because fuel pressure looks OK at noload.

3-proper diagnosis requires flow test or PSI under load.

4-got to drop tank and replace fuel intake/return.

 

Could be. He did say it was a nothern car. Also, it had been sitting, but I imagine that was because it had this problem and the PO didn't know how to fix it. I'm doing suspension work and such on my SE currently. I don't believe that I have this issue, but I'll drop the tank while I'm at it just for kicks. My car is a west coast car, and I don't have any exterior rust. Even when I replaced my fuel level senser (usually impossible because the little screws rust up), was no problem for me as mine had no rust. It will be interesting if I see the same thing.

Chris had drained the tank of the old fuel. He said there was a bit of sediment, but no real rust to report. I should have brought the camera and taken a pic. You would not believe how clogged it was. It was so packed that it was hard to jam a small screwdriver through it to break up the clog. No wonder she was starving for gas.

If you follow the FSM, you will not find this problem as they don't tell you to do a volume test (only a static pressure test). The pump and regulator pressure checked out. There must have been just enough flow allowed to return to the tank to allow for regulation (at idle). This is mainly due to the fact that the pickup was really clogged too (otherwise pressure would have been too high).

This is another example of how taking things step-by-step, you can eliminate possible problems. Once we found the low flow at the engine, we tracked it backwards until we had pinpointed the problem.

 

Good comments and I hope this helps all who have similiar symptoms...especially if you have a northern car or a car that has sit a long time.. Lets face it , a 24 year old car is going to have crud in the tank....its just a matter of how much.In my case, way to much....

thanks Kent...with out his help , who knows if I would ever had found the problem...


chris

 

One other thing that I should mention. On my SE, when I put a fuel pressure tester on, the pressure jumps right up to where it should be. On Chris's car, the fuel pressure went to spec, but I noticed that it was much slower to get there. It took a few seconds for the pressure to build. Again, an indication of either a blockage or poor pump output.

Chris had replaced the filter (new) and the fuel pump (used) to try to fix the problem. The issue still remained. It would have been possible for the replacement pump to be bad, but not likely. The shop that he took it to thought that it might be the regulator or the pump, but they didn't even bother to throw a gauge on to test the fuel pressure. They were just guessing. Doing the flow test at several points, working our way to the tank, allowed us to eliminate other possibilities until a clogged pickup was the only possibility.

It pays to be methodical and not just start randomly replacing parts and hope that the problem goes away. If you think it could be the fuel filter, for example, and you know that the filter is due for replacement, then go ahead and replace. Other than small maintenance/tune-up items, you really need to test before randomly replacing parts. It will save a lot of time, money, and frustration.

I can't wait to hear how well she runs once the tank is clean and everything is buttoned back up.

 

great info...thanks for the post.

 

I ran into this same issue on 2 seperate 12A cars. A 1979 with ~90K actual miles, and a 1985 with ~145K. Both had been allowed to sit for many years at a time, over the course of their life. The 79 tank and pickup tube were both filled with a layer of black goo that resembled tar. The 85 was just rust and scale.
The 79 was the real problem child, as we all know, they don't have tank drains nor removable pickup tube assemblies. It's amazing how fast a couple gallons of A/C condenser coil cleaner (acid based) ate up that black goo. Getting the pickup cleaned out required a bit more effort. The goo was so thick, it had the base of the pickup tube covered by more than 1/4", with a tiny hole that gas could be drawn thru. Car would idle fine, for hours, but as soon as you tried to drive it, it would die in about 1 block, when the carb ran dry........

 

What else could it be other than the rubber fuel line breaking down inside? Any chance that some of the fuel line was NOT fuel injection rated??

 

i don't know. It is a possibility. The lines near the tank are original (i'm sure) and were looking pretty shot. He got new lines to put on.

 

Does either the 12A or 13B have a neoprene hose immersed in the tank?

Over at the Alfa 164 club there's quite a bit of chatter because part of the fuel pickup is a flexible hose and it's hard to get the right stuff. Poor quality hose will deteriorate and cause obstructions.

 

It's a hard line. Believe all of the 7s are. The earlier ones (S1, S2) have pickup/returns that are part of the tank. The S3 cars have a removable plate in which all the hardlines (vent, return, pickup) meet the tank. The pickup up has a sock (plastic basket with a screen) to pre-filter. Now, I've been thining about this. The hardlines come in vertical, then bend horizontal, then back to vertical (all inside the tank). Above these bends is fuel hose (of course). These soft lines are by the tank (above rear axle) and I suspect that they have never been replaced in the majority of the cars on here. I can imagine, with 25 year old hose, becoming deteriorated. If the car is left to sit, the pieces of this rubber could flake, settle to the lowest point in the pickup, and build up. If the car is used all of the pieces never get the chance to settle, so might be less of a problem.

 

Good job Kent and Chris. Glad tp hear you guys figured it out. When I first got my 83 GSL, the PO said after the car had sat for numurous years, the only way he could get it to run was to pour a little gas down the carb. After that gas fizzled out, it would die. You could hear the fuel pump running, but no gas. Dropped the tank and you couldn't get a wire down the fuel hard lines. Replaced the tank, problem solved! My car sat in the PO's garage for 8-10 years. Kent has seen my car in person. No rust anywhere. So, I don't have a clue what causes the tanks to do this unless it's just the gas sitting and disolving the rubber lines.

 

Great info guys! I have two questions:

1. What should be used to clean out the tank?

2. About how much does it cost to replace the fuel lines?

Thanks,

Mike

 

No sure on the tank. I believe POR-15 has a kit to clean and seal the tank. You can also pull the tank and take to a radiator shop and they can clean it.

Fuel hose is cheap and pretty easy to get to once the tank is dropped. There are 3 different sizes. 1 for the feed, 1 for return, 1 for the vent. The feed and return need to be fuel hose for FI application. It will be quite a bit more expensive than carb fuel line since it has to handle higher pressure. The vent line can be regular emissions/vacuum hose.

I checked my lines. They look a lot better than Chris's. I haven't pulled the tank yet, so we will see on that one. Chris's lines looked like a sponge on the outside due to age.

 

FYI...I just bought a gas tank cleaning kit from KBS. I was going to use por-15 but they were a little more expensive so I went with KBS who had great reviews from others who used it... I will let you all know how it turns out. The kit was 67.00 shipped.

fuel lines ( the rubber hoses at the tank) are relatively inexpensive but like kent has siad, make sure you get the fuel injection hose. I franly did not know there was a differenec. I do now.
I can wait to get this car running!!!! I will let you all know asap.

by the way,a new tank is not cheap $350- 400 I am told ...or more...

 

New tanks can be bought here:

http://www.mazdatrix.com/c-pump.htm

About $465 for 84-85 tanks, $880 for 81-83

Certainly not cheap, but might become an option if you live in an area where all the tanks are rusted out and good tanks become hard to come by.

 

Hi,

I was wondering if anyone knew how to stop rust in the metal fuel lines or do they have to be replaced?

I took off the rubber hose and cranked the motor and the fuel collected in a jar was like mud water. I drained about a quart from the gas tank and did not see any rust or debris so I am assuming it is the fuel lines. Plus the fuel filter is after the fuel pump but before the metal fuel lines.

Would POR15 FUEL PRESERVATIVE & STABILIZER work?

Thank you in advance!

 

The hard fuel lines are aluminium (no rust). The stock fuel filter location is before the pump after the tank. You can look inside the tank with out dropping it. Remove the left rear wheel and the plastic panel at the rear of the wheel well. Remove the multiple small screws from the sending unit plate that you've uncovered. Remove the sending unit. You now have a 3" hole open into the gas tank. I used a camera to get a better view. The tank in this picture was cleaned and sealed with POR-15 gas tank sealer about two months ago. The rust flakes dropped in when I put the sending unit, fuel lines and fill tube back on the tank.

 

BTW, I checked my tank. Clean as can be. No blockage, pickup screen very clean, etc. My car has spent most of its life on the West Coast, seen little snow, and no salt.

 

Hi 74RX4,

I did not know the hard fuel lines were aluminum. I thought they were all steel. I'm assuming the rust must be coming from the tank then, but when I drained some gas, I did not notice any rust at all.

Could the rust be coming from someplae else?

Thank you!