Keeps fouling plugs?

[Technology]

Have you driven it on a day when it didn't rain? And quit spending money on stuff that won't fix the problem. It's the injector(s). Embrace the idea, and you will have good results.

[HurleyTSi]

Yes and it started up multiple times on the dry days that I drove it. But after every rain storm it wont start.

 

I'm not doubting in any way that it has a leaky injector or that the throttle body is in definite need of a rebuild just for how old it is and how it drives. I can tell it's running rich. But rain doesn't make an injector leak more lol :character0292:

 

Something must be getting wet. Its happened 3 times now and every time it's after a rain storm.

[shift1313]

Yes, you have a leaky injector. That will definitely cause those symptoms.

I like to run a one step hotter plug in my alternating injection cars. It starts better and runs better. These are stock boost (4.5 Lbs) non intercooled cars with a little lower compression from age. The hotter plug really seems to help them stay alive a few more years without rebuilding.

 

 

4.5 lbs of boost? is that factory? my gauge ran 7psi stock form and i though all the cars were 7 or 10.5 from the factory.

 

 

Hurley, under the hood really shouldnt be getting wet(just the humidity). What you need to do next time it wont start is have an extra plug on you and hook it up to see if you have spark. If you do its a fuel problem. If not at least we can focus on the issue. The ignition system has very few components but they all need a good ground(chassis near battery and ground on intake manifold).

[HurleyTSi]

Meh the car has more problems then just starting in the rain or even a leaky injector.

 

Had a compression test done and it was at around 20 on 2 cylinders. Even with a bit of oil on top of the pistons it was still way low. Either way I'm selling to a friend as a parts car. I dont have enough money to spend on a new motor rebuild. I just barely spent 800 for the bottom end rebuild on my Talon (not including the parts). So spending another 800-1000 on a car I paid 700 for doesn't seem practical to me. I could use that 1000 and buy another car instead.

 

It was a fun car I'll probably pick up another one down the road. Probably from someone on here because the cleanest ones are on this site and I'd like one as a collector's piece.

 

I didn't want to junk it because I'd rather see the parts from it help get another Starquest on the road. I also dont see much point in keeping one for a full-blown project when the body is in such horrible shape. It'll be a good parts car.

Edited June 20, 2009 by HurleyTSi

[FlattopMike]

You probably have a cracked or warped head. Not that big of a deal.

[Indiana]

One thing you may haven't though about is that you are in a RWD and its raining....ok do you drive exactly like you do when its dry out? You can boost and burn out some excess fuel from a leaky or poorly spraying dirty injector but if its wet pavement then you can't.......so you are back to dirty injectors which on your year fuel system are very easy to cause problems. On the 87+ systems you have ONE injector spraying and if just one is dirty and its say only 550cc then its not horrible, that is until you know what a cleaned one does lol, but you have TWO injectors that fire back and forth spraying from dirty injectors that each are about 850cc. See where this is leading? Its not a "bad" systems as some website claims, its just that its easier to have it cause issues from dirty injectors. No one said that TEP knew wth they were talking about anyway certainly not me.

[Tim_C.]

4.5 lbs of boost? is that factory? my gauge ran 7psi stock form and i though all the cars were 7 or 10.5 from the factory.

Yes, the non intercooled cars were 4.5 Lbs of boost OEM.

[shift1313]

Meh the car has more problems then just starting in the rain or even a leaky injector.

 

Had a compression test done and it was at around 20 on 2 cylinders. Even with a bit of oil on top of the pistons it was still way low. Either way I'm selling to a friend as a parts car. I dont have enough money to spend on a new motor rebuild. I just barely spent 800 for the bottom end rebuild on my Talon (not including the parts). So spending another 800-1000 on a car I paid 700 for doesn't seem practical to me. I could use that 1000 and buy another car instead.

 

It was a fun car I'll probably pick up another one down the road. Probably from someone on here because the cleanest ones are on this site and I'd like one as a collector's piece.

 

I didn't want to junk it because I'd rather see the parts from it help get another Starquest on the road. I also dont see much point in keeping one for a full-blown project when the body is in such horrible shape. It'll be a good parts car.

 

 

Just low Comp can be an easy fix. If it is a head you can pickup a stock used head for under $100, bare reman for $150-$180. Re-ring under $100 for rings and headgasket.

[FlattopMike]

Yes, the non intercooled cars were 4.5 Lbs of boost OEM.

 

My 83 runs 7lbs stock.

It is my understanding from everything that I have heard and read that 7lbs was stock for non-intercooled and 10lbs for intercooled.

[shift1313]

mine was between 6-7 on the gauge when i got it. It was bone stock as well. Ive read 7.5psi and 10.5psi as well. that 4.5 was new to me but im going by what ive read on the internet

[Bill Hincher]

IF you have a functioning EGR valve, you will find that its open under cold engine conditions ( for what ever reason)

if the EGR is open during cold start , it creates a vacuum leak to the closest cylinders and fouls the plugs on cold morning starts

 

the first time I saw that was in 1986 on a Honda Accord and drove me nutz

[Tim_C.]

Nope, the pre '87 non-ic cars with batch fire injection were all 4.5 lbs of boost from the factory. '85.5, '86, '87 intercooled cars were 7 lbs. '88, & '89 were 10 lbs.

I don't know about the '87 non-ic cars with a primary and secondary injector.

Your cars may have been higher for various reasons, but they were supposed to be 4.5 from the factory. Different altitudes, vac leaks, etc.. can change the same car's boost level. The wastegate actuators may move the arm a little different over time, etc...

The factory gauges are not so accurate either.

[FlattopMike]

The specs on my 83 service manual say that my waste gate actuator operating pressure is 58 kPa.

The conversions in the same manual say the 1 KPA = .1450 PSI.

That means that the waste gate actuator operates @ 8.41 PSI.

Edited August 5, 2009 by FlattopMike

[Dave-O]

What I find entertaining is, the same Conquest in question is now mine, and starts/idles perfectly fine on two cylinders. Cold start, hot start, doesn't matter. Fires right up every time. Nothing has changed since HurleyTSi has had it.

 

I pulled the wastegate line and took it for a drive the other day, just to see what would happen - spiked to 11psi at 5500rpm and pulled rather decently for [what felt like] 2 cylinders. Took until just after 4500 for the turbo to even spool, haha.

 

I'll be pulling the new [to me, pulled from an '88 Auto Conquest] engine out of my Starion [it's technically just sitting in there] and swapping it into the flatty, along with my Starion's OEM LSD for the time being. I've got a few things I want to do with my Starion before I can drive it, and the Conquest runs/drives as-is, so why not

[FlattopMike]

What I find entertaining is, the same Conquest in question is now mine, and starts/idles perfectly fine on two cylinders. Cold start, hot start, doesn't matter. Fires right up every time. Nothing has changed since HurleyTSi has had it.

 

I pulled the wastegate line and took it for a drive the other day, just to see what would happen - spiked to 11psi at 5500rpm and pulled rather decently for [what felt like] 2 cylinders. Took until just after 4500 for the turbo to even spool, haha.

 

I'll be pulling the new [to me, pulled from an '88 Auto Conquest] engine out of my Starion [it's technically just sitting in there] and swapping it into the flatty, along with my Starion's OEM LSD for the time being. I've got a few things I want to do with my Starion before I can drive it, and the Conquest runs/drives as-is, so why not

 

I would find out why the 2 cylinders are low.

My money is on a warped head and could be fixed without a lot of time or money.

[Dave-O]

The engine will definitely be rebuilt. There are good-running carb'd G54Bs everywhere around here that I can pilfer a head from, if that is in fact the case. If there's piston damage, I'll order up an aftermarket forged set. If it 's just rings, it'll get re-ringed and tossed back into the car.

[Tim_C.]

The specs on my 83 service manual say that my waste gate actuator operating pressure is 58 kPa.

The conversions in the same manual say the 1 KPA = .1450 PSI.

That means that the waste gate actuator operates @ 8.41 PSI.

Maybe the '83 is different, but I highly doubt it. There is no way the intercooled version went DOWN in boost pressure. The reason they went intercooled is to have the ability to increase the pressure, and increase it they did. I am not home now, but I have an '83, '84, 85, 87, and an 88 manual. I will check them to get the actual pressure, but there is no way a non intercooled car was set to 8.4 PSI of boost from the facory. If that is in the manual, it is a misprint because the intercooled version in 85.5 increased the boost from 4.5 to 7 PSI. That was advertised. I believe you may have read the wastegate actuator is fully open at 8.4 PSI? They were all 4.5 Lbs from what I remember reading in the manuals, and all 3 of my running flatties reflected that. I since put an intercooler on the CBRII and run 10 PSI with no problems, but 7 without the intercooler would detonate and it was running rich and timed moderately, etc.... Same on my '85 non-IC with 50 PSI of baseline FP. The fuel charge heats up way too much to run much over 5 safely, so people can run higher but I garantee you the parts can't take it.

 

I will say that I am at high altitude and could possibly be wrong, but what others are saying about the boost level makes no sense and I know for a fact it was advertised as being increased from 4.5 to 7 in 85.5. They also documented the increased lag from the IC piping in the same ad.

[FlattopMike]

I quoted the manual exactly and I know that my non-intercooled 83 shows between 7 and 8 pounds without a boost controller on my after market gauge.

[Tim_C.]

I quoted the manual exactly and I know that my non-intercooled 83 shows between 7 and 8 pounds without a boost controller on my after market gauge.

Yes, I read the same thing in mine.

What the boost reads now says nothing about what it was from the factory. Even though I posted my numbers too. If an '83 came with 8.4 Lbs of boost, then that that is why it was lowered to 4.5. The fuel charge would have been too hot & cause damage to the engine. It may run a little cooler at low altitude and high humidity, but the risk of detonation at dry high altitude would be way too great. That would have been a definite design flaw.

 

If you are running 7.5 on a fully stock '83 then that would be very surprising. The turbo heats up the charge way too much for that without at least an opened up exhaust.

 

My '84 manual says the same numbers.

The '88 manual doesn't say anywhere that I see so far. It only says to check the wastegate actuator, you need to apply 3PSI of negative pressure and check for leaks.

I know Prof Quest used to post it was 4.5 PSI for all non-intercooled boost levels. I know the 85.5 advertised raising the boost from 4.5 to 7 with the addition of the intercooler.

The non-intercooled turbo is essentially the same size as the intercooled one. Maybe rated 20CFM less at 15 PSI. Raising the boost on such a small turbo increases heat at a dramatic rate. Increased heat = detonation. It has been my experience at 6000' altitude with dry humidity that much over 5 PSI can start to detonate, depending on the gas used, and outside air temp. On cold days (30F or below), I'm sure I could safely increase the boost 1 PSI due to the cold air coming through the air filter. That is much more so on an intercooled car that you can feel a dramatic power increase at those same temps, thus having the ability to increase boost substantially.

Detonation can be very subtle to where you don't realize it on these cars. I really don't know how, because it is also more severe on a long stroke engine. I think the increased bore size dissipates the feel of it moreso. I don't know, but I have blown an engine from detonation and never felt a thing. That was on an intercooled '87 TSi at the stock 7PSI boost level. I had a fuel issue for a very short period of time that I did not detect in time. My '85 non-intercooled car with straight through 2.5" exhaust, was running rich at about 6 - 7 PSI and detonated for 5 seconds and blew the ring lands on a hyper-u piston. I was pulling hard and simply felt a slight hesitation. I let off the throttle, but it was too late. Thus my 'better safe than sorry' approach and the same advice to anyone who thinks they can safely raise the boost on a non-intercooled car beyond 5 PSI without other mods.

[Dave-O]

On the topic of non-intercooled / intercooled differences ... was there a change in the fuel system or ECU between non-i/c and i/c'd flatties? I plan on running the fatty intercooler and turbo on my new engine with the original 85 fuel system and an open exhaust - keeping timing in check, would 10psi be asking too much of the fuel system?

[FlattopMike]

On the topic of non-intercooled / intercooled differences ... was there a change in the fuel system or ECU between non-i/c and i/c'd flatties? I plan on running the fatty intercooler and turbo on my new engine with the original 85 fuel system and an open exhaust - keeping timing in check, would 10psi be asking too much of the fuel system?

 

You will need to eliminate the fuel cut but it should be able to handle it.

[Dave-O]

What pressure is the fuel cut supposed to actuate at? Looks like I'll have to do some reading on an FCD.

[Tim_C.]

My '83 did not have a fuel cut. Shelby told me he ran an intercooled '83 with stock fuel system except for increased baseline pressure to 55 or 60 PSI (can't remember which), and 18PSI of boost with no problems.

 

As for the '84 & '85, I don't know for sure. I'd have to research my manuals.

[Dave-O]

I guess I'll toss everything together and run off the stock fatty wastegate. if it cuts, not much I can do. I'll borrow a wideband and see what the afr's are. I don't intend to go MPI, so a fuel-only Megasquirt might be a good investment.

[Tim_C.]

I guess I'll toss everything together and run off the stock fatty wastegate. if it cuts, not much I can do. I'll borrow a wideband and see what the afr's are. I don't intend to go MPI, so a fuel-only Megasquirt might be a good investment.

That reminds me of a very interesting thing that I completely forgot about. I have adjusted my '87 TSi single port wastegate to where it would open at 5 PSI boost on an aftermarket gauge. Incidentally, my stock gauge read the same as my aftermarket one on that car. I would think you can adjust the threads on the actuator arm to give it more travel to open more and reduce boost like I did on that one. I don't have the perfect explanation as to how that is, but I could adjust that single arm from below 5 PSI (still threads left, so I assume it would have gone further), to above 17 PSI.