I've got a 93 del sol with the d16z6. After I start the car, one or two minutes down the road it will bog. If i let off the gas and go back on the gas it'll go away for a couple seconds and the return. Also if I floor it, it'll go away, but when I let off again it will come back. After a minute or so it'll work itself out and will drive absolutely fine. Now this bogging happens regardless if I'm driving in town or going 60 down the highway. It also doesn't matter what temperature the engine is. It used to do this rarely, but it's become more frequent, and now happens every time I start the car. I thought it had to be fuel pump. But I just replaced it and nothing has changed. So what could be my problem??

 

When was the last ignition system tune up done? Any CEL codes?

 

No cel's. I replaced cap and rotor and well the whole distributor about 5 years ago. However today when I tried to start it the fuel pump didn't come on. Tried turning the key a couple more times and it started working.

 

5 years is a long time.

 

I'll check it out.

 

But regardless of ignition system, what would cause the fuel pump not to run?

 

How is your fuel pump not running if you're driving it around town?

 

Resolder the main relay.

http://techauto.awardspace.com/mainrelay.html

 

The fuel pump doesn't prime sometimes when you turn the key.

Getting new plugs and checking out the distributor today.

 

Why would you expect replacing the plugs or distributor would have any effect whatsoever on the fuel pump priming?

Focus here: MAIN RELAY

 

Listen to ron he knows what hes talking about

 

The plugs and such needed replacing anyway. So main relay it is.

 

Before you spend money clean the ground wires bolted to the thermostat housing. This is where the main relay is grounded thru the ECU and will effect the fuel pump priming problem. Once it's running the bogging problem may be due to the IACV screen being clogged. See FAQ section for cleaning this. One other thing I did was raise the base idle with the IACV electrical connection disconnected. I went to 750 RPM instead of 450 (auto).Then reconnect the electrical connection. Now I have no bogging even with the AC on. The car takes off from a dead stop with no stuttering.

 

So replaced the main relay, still the same problem. But seems not as bad. Cleaned the ground on the thermostat, which didn't seem to be bad at all. Still the same problem. So now its on to cleaning the IACV. Hopefully this does the trick!

 

Okay so far these are the things I've done to fix this problem:

Replaced the fuel pump
Replaced the main relay
Cleaned IACV
Replaced cap and rotor and spark plugs
Cleaned the thermostat grounding point

Still have the exact same problem. However the main relay seemed to fix my non priming fuel pump problem.

Any more ideas?

 

Hooked up my fuel pressure gauge today and the pressure doesn't go down when it bogs, stays right where it should be.

So this can't be fuel related, or can it?

Any ideas??

 

Anyone?

 

I'm trying to understand what you're experiencing, I had a problem of what I assume is similar to what you are having. It ended up being that the fuel tank was rusted from this inside. I had to replace the tank and obv clean the injectors etc... I doubt this is what's wrong since you said you replaced the fuel filter, because you should have notice abormailites. Anyway I thought I just offer some food for thought, maybe it's something similar with the fuel. Good luck man.

 

I actually haven't replaced the fuel filter in some time. The reason i don't think its fuel related is because the fuel pressure doesn't drop at all when it starts bogging down. It bogs pretty regularly. Meaning it will do it a couple minutes after starting the car, and then clear up after a minute or two of bogging, no matter what kind of driving I'm doing. Maybe I should clean the injectors and replace the fuel filter anyway?

 

Yeah I would, it just sounds all to similiar to what I experienced. Does it bogg harder when you give it a lot of pedal?

 

yeah i would replace the fuel filter

 

Yep, it'll bog a lot and then just snap back to normal.

 

This sounds wayy to similar to what happened to me. I eventually checked my fuel pump and it was clogged with rust. I replaced the tank and cleaned the injectioors and ran like new.

 

So! An update to my issue. Driving home last week the check engine light goes on and there is no noticeable drivability difference. It goes off and stays off when i turn off the car and start it back up. It came on only a few times since then with the same result. Yesterday, driving home from work the car just dies while pulling away from a stop sign. Check engine light was on. Kicked the main relay and I was able to drive it home. It cut out a couple times but continued to run. This morning it wouldn't start and the fuel pump either didn't prime or made a weird buzzing noise. It started finally and then died again when pulling out from my driveway. Same issue. The code? 43 Fuel Supply System. Warrantied the Main relay I got a couple months ago and that is where I am currently.

I've read that Code 43 usually means primary o2 sensor. But could also mean FPR, Fuel filter (replaced), Injectors, or fuel pump. I will update this when I put the main relay back in.

 

So put in the new relay, and it didn't prime, and had a check engine light. Checked the code and its code 43. Cycled the key again and the fuel pump primed. No check engine light. Cycled the key a couple more times and it would prime, prime, prime, prime, and then not prime, not prime, not prime.

What couple be causing it to prime sometimes and not others?