So Ive been having trouble with my car sputtering and backfiring and I just cannot figure it out. I have a 1.7 FI. When i rev the car under load it seems like it just has no power. Cars been timed correctly, went through everything and I still cannot figure it out. Hoses look ok, exhaust bolts seem to tighten but wont tighten completly. Not sure if this would cause all these problems or not. Could my injectors be clogged or fuel pressure be to low? Can someone go through a test procedure for this? I really don't want to have to spend another 3 or 4 hundred dollars on this if its just something simple. Thanks Guys

Matt

Have you tested your injector flow by disconnecting one at a time and putting it in a plastic jar while turning the engine over? Do you have a pressure gauge to check fuel pressure? Are you sure your fuel lines are correctly hooked up?

Im pretty sure all the lines are correct. I know if you have these fuel lines backwards or wrong the car will not run and ive gone through a couple gallons of gas already.
Can you explain what I would need to check the fuel pressure? WHere Do I discconect the line to hook up a fuel pressure gauge? What should the proper pressure be for the injectors?

clean the trigger points in the base of the distributor.

Ive cleaned the distributor and points very well..

This wont fix the sputtering or backfiring but may help the lack of power on acceleration.

1 drop of 30 wt on the felt pad under the rotor inside the shaft will lube the mechanical advance weights and should be done annually.

Sounds like a fuel deliverly issue. Check the pressure, check the fuel filter, check for trash in the lines, check the injectors. If you have no power and it is back firing, likely fuel related.

Im pretty sure all the lines are correct. I know if you have these fuel lines backwards or wrong the car will not run and ive gone through a couple gallons of gas already.
Can you explain what I would need to check the fuel pressure? WHere Do I discconect the line to hook up a fuel pressure gauge? What should the proper pressure be for the injectors?

T in to where the cold start valve is. That's an easy way to do it. Or, if you have a "spare" fitting on one fuel rail or another, you can just run a hose from there to the gauge.

Pressure should be 29 PSI.

--DD

Do you know if each plug is firing? What do your plugs look like. Are they black or look dry as a bone? Do they all look the same? With it running can you pull one plug at a time. Well not the plug but the wire to the plug. Pulling each wire in turn should help isolate a plug that may be causing trouble. You've probably allready done this but it's a simple thing to check

You can make a fuel pressure gauge from Home Depot parts; they sell a pressure gauge in the plumbing dept and brass fittings to allow you to clamp on a piece of fuel injection hose. Then follow DD's post...

This sounds just like what my car was doing when the fuel filter was getting full of crap. My gas tank wasn't the cleanest and this happened twice, and both times it was the filter junked up. I put in a filter with a replaceable element and once I swapped it out it went back to running fine. I also previously installed a fuel pressure gauge, so I could see the resulting drop in fuel pressure as well from the clogging.

I'd start there if you don't already have the stuff to check the fuel pressure, unless you changed the fuel filter recently.

to expand a bit. matt's issue is he told me that the car ildes fine but under load the the backfiring issue starts. prior to painting he had the car media blasted and the grit syndrome is evident. he showed me the dist cap that had been in the car and there was severe arching on the contact posts.

1. i think you need to verfiy your getting the full advance the engine requires. if you're going to farm out the work, have this done by a pro. the charge should be a minimum amount.

2. the cap swap made 0 diference. yes? what was the condition of the rotor?

3. go thru the box of hoses i gave you, find the appropriate one for the vac adv canister and swap it out. examine the MPS vac signal hose and make sure the ends fit tightly. cut the ends back slightly if the fit is sloppy. test for operation after every move you make.

3. check for good spark on each spark plug and correct gapping.

4. as i suggested, do the injector seals. if the phenolic spacers (gaskets) have never been replaced, get NEW ones. these items combined will set you back $21 and then you can rule them out as potential problems. pelican has them. if you take your car to a shop you'll dish out whatever they charge a hour to troubleshoot these very items. or they'll just throw parts at it and bill you accordingly whether needed or not.

5. how tattered are the plenum to intake runner tubes. sloppy loose or a snug fit?

6. the issue with the heat exchanger nuts is troubling. get the Aero-Kroil or PB Blaster. replace the copper gaskets 4 for $6, and get the correct nuts one time use, $.50 each @ pelican. use the torque wrench approach for removal to help insure you don't break studs or strip the threads in the heads.

7. you have to be systematic in your approach. one fix at a time.

k

So decided to try replacing the fuel filter and see what that does. So the smaller line coming from the tank that would that go on the inlet side of the filter correct? I don't want to mix that up. Thanks guys

Matt