easier said than done. I have limited time to work on this car as it is with son at college 280 miles from home. Maybe during summer break when he is home.

Yeah its quite a job... You can sorta check the injectors with a screwdriver, press the tip down on each injector and stick your ear near the handle, should be able to hear them tapping. Listen for any inconsistencies.

To me it seems to be a failing sensor somewhere. MAF would be a thing to check.

bc of the original thing my son said, when it 1st acted up he could hear the fuel pump making more noise than normal, that leads me to think either pump, or pump controller. tried pump, now controller.

This is a really wild guess but it is an easy item to check. I have a 90 NA Auto and had a similar experience several years ago.

After warming up, the engine would surge under acceleration, violently when under heavy load, and seem to misfire at steady cruise throttle settings. The engine wouldn't die and it would idle (although erratically) but climbing up a grade was like riding a bucking bronco. Drove OK while it was cold.

In my case, the culprit was a failing rubber fuel line section of the fuel rail where is crosses the top of the engine. When I inspected the line, it felt really soft and with increased engine RPM, it ballooned up on the bottom side. It was failing internally I believe, as it didn't show any external signs of cracking. It was probably close to opening up and dumping fuel onto the engine. I think in my case that under high demand, the line was preventing consistent fuel flow/pressure to the throttle bodies. I actually thought if the line were weak, it would collapse as opposed to balloon, but what happened was as I have described. In any case, I replaced the line and the problem went away.

Anyway, that was my experience. Doesn't take but a minute to look at the hose. It is the longer one on the upper side of the fuel rail on the passenger side of the engine. If it's leaking, feels weakened/soft or balloons with the engine running, it might be the issue.

Just an idea that is really easy to check. Good luck with solving the issue.

A somewhat more involved idea is to check and clean the CAS. Mine was contaminated with bearing residue (I think that was the material) and it gave me an unusual failure; misfire caused by a single cylinder loss of ignition pulse with an onset time varying with OAT.

just got the pump controller delivered. Had my son start the car 2 days ago and he said it was idling higher than normal and check engine light was on so he shut it down. Next weekend will travel to install the controller and will look at a few other things.

this past Friday night I installed the new/used fuel pump controller I got from Z1 Motorsports. Took like 10 minutes. Car fired right up. We put about 30.miles on it that night putting different loads on the engine. Parked the car over night then Saturday morning put another 30 miles on it at different loads. Lots of high revs and loading it up in city traffic. So far so good. fingers crossed.

been a week so far and no issues

update, son drove home almost 300 miles today. car was fine til a very tight loop interchange to switch interstates. had to wind out 2nd gear, to 5000 rpm in 3rd and 4th, got into 5th and lost throttle for a second or 2 then came back. this interchange is about 40 miles from home. Same spot where everything originally started. the last 40 mules car ran fine. when he got home the car idled around 1500. he blinded the throttle a couple times to get it to come down, once it came down the car stalled. he said it would start up again fine but idled at 1500 and would go back down so he shut it off. So far I have installed a replacement style fuel pump and a used pump controller from Z1. any thoughts. It seems like it acts up mostly when the car has been driven a long distance and under a big load

son just told me that a couple days ago they had a hot day at school and the fuel pump was louder than normal.

we just fired up the car after sitting for 2 days and only ran it for a few minutes. Idle seemed fine for a cold start but there was a bit of a gas smell from the engine bay and son said he could smell it sitting in the car. don't see any fuel leaks in the engine bay at all. is there a charcoal canister on this car

Fuel vapor in the car could be a bad seal on the tank pump flange plate and/or damage to the hoses at the tank end. Fuel smell in the engine bay is usually loose fuel hose clamps at the filter, regulator, damper, or clogged carbon canister. Also old dryrotten lines.

just changed the pump and installed new o ring. Also just changed filter and just happened to check clamps. I know those are good. I tried looking for the carbon canister. Where the he'll is that thing. I saw online that it's on driver fender behind inter cooler. Son's car is non turbo. Is it under the headlight in front of the radiator core support or something? I'll have to root around and check all the clamps and closer look at fuel hoses. Son only has a couple more weeks of school then will be home for the summer so we should be able to take care of some things.

Canister is under the left (DS) headlight, in front of the wheel well liner. Recheck the clamps, you've cycled them with pressure since installing which will work them off if for example the clamp was installed partly over the flare or if the temperatures outside have had any major swings.

Son drove car 300 miles back to school. He said when he got back the idle was wonky again, meaning like 1500 and the car stalled a few times so he parked it. This really seems like something is getting effected by heat soak. Could I have gotten a bad pump controller from Z1?

So son drove the car today and acted up bad. Wont idle. Son called Z1 and they said sounded like idle air control. Any thoughts.

Unplug it and see what it does

going to get the car back from son tomorrow and will start fiddling with the intake tubes and the idle air control valve and hoses

removed and cleaned the idle air control valve. what a pita to remove. To be honest the inside of the valve was pretty clean. just a lil black coloring but no serious carbon. car only has 80k on it though. no way I could get the stupid metal clips off the 2 plugs in the car so I cut the wires and will splice back together. plugs themselves are in good shape though. will report back later

have done the boost leak (car is na) and fixed multiple leaks. Loose clamp on driver side intake tube near max. Leaky vacuum hose on driver side. Trimmed hose and replaced clamp. changed orings for crossover tube since the bolts that went I to the manifold leaked. IACV was leaking where the gold colored round piece fits into the aluminum body. Took it apart (had to drill a lil pin out, replaced with roll pin) cleaned everything up, used red loctite to seal the gold part and installed roll pin. Let loctite dry over night then epoxied around the seam. Currently don't see any more leaks but car is still acting up. Running out of ideas. I don't THINK it's an injector issue but will be looking those up tonight

Just put the ecu into diagnostic mode. Car is a '96 with OBD2 but it does have the lil nob on the ecu. Went through the steps for diagnostic and only got code 55 which is no faults. Anyone?

Just took car for quick drive. While rolling basically at idle I hit the gas to the floor and car bogged. Stopped at sign leaving neighborhood. Got rolling again about half throttle and was fine shifted into 2nd and floored it and it bogged. Acted like this on and off during quick 10 minute drive. currently idling ok and no cel. Also, using a long screw driver it seems like all injectors are pulsing. Now whether or not they work properly all the time is another question

So have found to corroded connectors in the engine bay.

I ordered a set of injectors. Waiting for delivery.


Son read that all of his symptoms points to the TPS. We tested the TPS and all is good. Tried to check for continuity across the 2 pins on the TPS for the hard idle switch. Didn't get anything on the multi meter regardless of how I attached the test clips.

Will be looking into the MAF tomorrow.